Nanoengineered biophotonic hybrid device

ABSTRACT

An improved method for the design and development of high performance hybrid devices having biological and nonbiological components. The biological component is used in hybrid constructs that may be nanostructures, given the small size of the biological parts. In one specific embodiment, chlorosomes of  Chloroflexus aurantiacus  ( C. aurantiacus ) enhance performance of a silicon photovoltaic cell.  C. aurantiacus , strain J-10-f1, has the A.T.C.C. designation number 29366, having been deposited in July, 1976. Its chlorosomes are harvested and positioned in light communicating relation to a photoactive semiconductor. The chlorosomes react to light of a first wavelength by emitting light at a second wavelength to which the semiconductor electrically responds.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-in-Part application off of U.S.application Ser. No. 11/475,342 in the name of Jeffrey T. LaBelle andVincent B. Pizziconi, filed Jun. 26, 2006, entitled “NanoengineeredBiophotonic Hybrid Device,” now abandoned, which claims priority fromthe divisional U.S. application Ser. No. 10/658,541 in the name ofJeffrey T. LaBelle and Vincent B. Pizziconi, filed Sep. 8, 2003,entitled “Nanoengineered Biophotonic Hybrid Device,” now U.S. Pat. No.7,067,293, issued Jun. 27, 2006, which claims priority from provisionalU.S. patent application Ser. No. 60/408,775, of the same inventors,filed Sep. 7, 2002 entitled “Method & Apparatus for Synthesis,Processing, Design & Manufacturing of High Performance, Scalable &Adaptive, Robust Energy-Interactive Materials, Devices & Systems.” As tosubject matter in this application common to one or more of theforegoing three applications, priority from each of the foregoing threeapplications is hereby claimed. Each of the foregoing three applicationsis incorporated herein by reference.

This application is related to three concurrently filed applications,each in the name of the present applicants and all sharing priority fromthe above-identified provisional and parent U.S. utility applicationSer. No. 10/658,541. The three concurrently filed applications areentitled “Device With Biological Component And Method Of Making ToAchieve A Desired Figure of Merit,” Ser. No. 11/475,343, “Device WithBiological Component And Method of Making To Achieve A Desired TransferFunction,” Ser. No. 11,475,338, and “Method Of Making BiologicalComponents For Devices By Forced Environmental Adaptation,” Ser. No.11/475,356.

STATEMENT OF GOVERNMENT FUNDING

Financial assistance for this project was provided by the U.S.Government through the National Science Foundation Under Grant Numbers9602258 and 9986614 and the United States Government may own certainrights to this invention.

FIELD OF THE INVENTION

This invention relates to hybrid biological and electronicphotosensitive devices and more particularly to nanoscale hybrid devicesof this kind and their method of manufacture.

BACKGROUND

Recently, attempts to marry biology and engineering to create variousbiohybrid constructs have been steadily increasing. A limited number ofnovel biohybrid sensor applications have already been reported, and insome cases commercialized, that incorporate “smart” molecular-scalebiological components. These have attracted considerable interest fromboth the biomedical and biotechnology communities worldwide. However,little has been done to date in developing integrated nanodevices andsystems such as microanalytical systems incorporating novel, engineerednanobioconstructs and their analogues for use in integrated nanodevicesand systems such as bio-optical hybrid sensors capable of very sensitiveand selective nanoscale detection due to enhanced performancecharacteristics as determined by a prescribed biohybrid Figure of Merit(FoM). Potential applications include microsystem applications requiringlow-level light detection capability (e.g. micro total analyticalsystems (μTAS) for immunoassay, genomics and proteomics), such as“point-of-care” diagnostic medicine, biotechnology, spacebioengineering, and countermeasures to biowarfare for defense.

In general, the current state of art for engineering design as taught byKoen (Koen, 1987) and many others (Otto and Wood, 2001), has not led tothe achievement of device components, stand-alone devices, norengineered systems that function or otherwise perform at a prescribedFoM and oftentimes typically perform at levels significantly belowoptimal FoM levels and theoretically achievable maximum FoM limits.

The well known area of thermoelectric device design exemplifies thepresent ability of engineering design heuristics to achieve a desirablethermoelectric FoM (i.e., ZT) that significantly exceeds current ZTdevice values of ˜1 although a ZT value of 4 is theoretically possible(Rowe, D. M., 1995). The present inability by those skilled in the artto achieve desired material and device FoM's is essentially true forvirtually all engineering device design applications spanning diversedisciplinary fields and broad industry product segments.

In recent years, less effective and predictive empirical approaches havebeen used to devise novel hybrid devices that incorporatenaturally-derived, or mimetics thereof, biological materials andconstructs that have resulted in enhanced device performance relative totheir non-hybrid engineered counterpart. To date, however, theengineering method does not teach how to design, select, modify orotherwise alter smart, nanoscale energy-interactive materials (e.g.,molecular-scale biophotonic components) derived from natural orbiomimetic analog constructs, a priori, in spite of their intrinsicallysuperior and potentially adaptable structural and performancecharacteristics. Nor does the engineering method show those skilled inthis art how such nanoscale materials can be further embodied oremployed as components, or as stand-alone devices, that are capable ofproducing robust and scalable energy-interactive biohybrid devices andsystems, a priori, to function at a desired FoM not yet achievable byconventional engineering means.

Photoactive semiconductors such as Si photovoltaic cells (as one exampleof a large scale device) have long been known. They have been employedin various devices and applications for years. Their varyingresponsivity to certain light wavelengths throughout the visiblespectrum has been observed as well. On the biological side, thermophilicphotosynthetic bacteria such as Chloroflexus aurantiacus (C.aurantiacus) and other species have been studied and reported upon. Thephotosensitive “antenna” structures, “chlorosomes,” of these organismshave been studied and reported upon, as well. Perhaps as a result ofinconsistency of results with photosynthetic bacteria, these organismsand their chlorosomes have not been incorporated into useable devices.There has been no successful synthesis of photosensitive semiconductormaterials with the chlorosomes of photosynthetic bacteria reported. Aneed exists for improvement of the performance of photoactive devicesthroughout the light spectrum, and for techniques for using the goodphotosensitivity of photosynthetic bacteria in photoactive devices. Morefundamentally, there is a need to identify inconsistencies in thephotosensitivity (or other photonic or electroactivity) of biologicalspecimens and to apply a method or methods to ameliorate or eliminatesuch inconsistencies.

As one means of gathering knowledge about a system, Design of Experiment(DOE) analysis is a widely used statistical modeling approach, reportedin detail elsewhere (Montgomery, 1991). A unique advantage of DOE,particularly as applied to complex adaptive systems, is its ability toelucidate, not only the effect of the controlling variables, but alsotheir complex interactions. Use of DOE analysis with biological orhybrid biological/nonbiological devices and systems has not beenencountered. In particular use of the powerful DOE approach inconnection with forced adaptation in biological systems (such asbacteria) to move the systems toward a more consistent (i.e. dependable)performance is not known. Figure of Merit (FoM) is another concept oftenused in engineering (among other fields such as economics, chemistry,astronomy, etc.). FoM is a measure of a device's performance. It is usedin many contexts. However FoM as a design-driving measure, particularlywith respect to adaptive biological organisms-based systems, devices andcomponents is considered to be a radical departure from other uses ofthis concept. Further, as applied to biological organisms, parts thereofor systems made up of such organisms, a means to control multipleenvironmental variables is needed if the DOE approach is to be applied.

The transfer function of a device, circuit or system is anotherengineering concept that is well understood. However, that concept hasnot ordinarily been applied to biological systems, if at all. A needexists to apply engineering concepts like DOE, FoM and the transferfunction to the analysis, evaluation and design of biological,bioengineered and hybrid systems, components and devices.

SUMMARY

Broadly, the present invention encompasses equipment and methods for thesynthesis, processing, design and manufacturing of high performance,scalable, adaptive and robust energy-interactive hybrid materials,devices and systems combining biological and nonbiological technologies.Specifically, an exemplary embodiment of the invention adapts powerfulengineering concepts to the engineering of biological components thatare to be used in manufactured devices and systems, including hybriddevices and systems.

FIG. 1 exemplifies a novel method that will guide those skilled in theart to achieve the design and development of high performance hybridmaterials and devices. As illustrated, several key steps are depicted inFIG. 1 that show one skilled in the art how to achieve desired and evenoptimal hybrid device designs that utilize smart, nanoscale constructsacquired, harvested or otherwise derived directly from complex livingorganisms. A preferred embodiment is the use of a multipleinput-multiple output apparatus, such as a multiple input-multipleoutput environmental chamber (i.e., MIMO/EC), and applicablecomputational algorithms to extract useful and exploitable hybrid devicedesign heuristics. Use of this method will result in a desired andprescribed Figure of Merit in spite of the use of previously unknown orpoorly defined or characterized nanoscale biological constructs andtheir function. In applied form, the novel engineering design methoddescribed herein will provide a means to identify or otherwise exploitintractable, or very difficult to identify, useful engineeringspecifications. A preferred embodiment of this invention is shown inFIG. 2, an illustration of a novel method and apparatus for the designand development of high performance hybrid materials and devices. Oneapplication of the proposed invention is the enhancement of well-knownphotoactive semiconductor devices, such as Si photovoltaic cells usingnanoscale biophotonic constructs that are either acquired, harvested orotherwise manipulated in their natural or adapted state using the methodand apparati described herein to achieve desired FoM performancecharacteristics. Although commercially available Si photovoltaic cellshave been employed in various devices and applications for years, theirFoMs are typically low despite detailed knowledge of their structure andfunction and the ability to prescribe device performance specificationsfrom use of selected light wavelengths throughout the visible spectrum,as well as, related device specifications associated with theengineering transfer function.

The transfer function of a component, device, or system is a usefulengineering concept, directly related to the FoM, that is well known andunderstood by those skilled in the art. However, the use of a transferfunction and related FoM concepts have not been generally applied andprescribed to biological constructs intended for use in the design ofbiohybrid devices and systems, if at all. Thus, an unmet and nonobviousneed still exists to use well known engineering heuristics such as, thedesign of experiments (i.e., DOE), FoM and the transfer function for theanalysis, design, and evaluation of bioengineered hybrid components,devices and systems.

To demonstrate the novelty and utility in the use of the hybrid devicedesign heuristic to achieve high performance hybrid materials anddevices (FIG. 2), the invention described herein improves the deviceperformance (i.e., the FoM) of a stand-alone, commercial siliconphotovoltaic device (Si PV) using a nanoscale bioderived construct withgenerally unknown engineering specifications. However, the methods andapparati taught herein generally apply to the design and exploitationany smart nanoscale or integrative nanoscale material, construct, orsystem, or mimics thereof, that is amenable to the FoM enhancement of ahybrid device or system.

A typical FoM of a Si PV device is generally less than 1 and typicallyonly ˜0.28-0.32. Although a number of potentially useful hybrid designapproaches can be employed to improve the SiPV FoM using the inventiontaught herein, the use of a nanoscale biophotonic construct havingdesired complementary energy transfer properties constitutes apotentially viable hybrid design approach. One such nanoscalebiophotonic construct having potentially useful and exploitableengineering specifications to enhance the FoM of a photonic device, suchas a SiPV device, is the nanoscale pigment-protein supramolecularconstruct known as a light antenna structure that functions as an energyfunnel in thermophilic photosynthetic bacteria such as Chloroflexusaurantiacus (C. aurantiacus) and other photosynthetic species. Thesehighly quantum efficient photosensitive constructs (also known as“chlorosomes”) are known to perform significant photonic energy shifts(red shift). In the case of the chlorosome associated with the C.aurantiacus, an input photonic energy at a wavelength of ˜460-480 nm istypically shifted to ˜800-820 nm with very little energy loss.

Typically SiPV devices are more sensitive to higher photonic wavelengthsand generally most sensitive to the near infrared region (i.e. 800-900nm) of the electromagnetic spectra. Thus, in principle, the use ofbiologically-derived light antenna structures, as well as mimics oranalogs thereof, could potentially enhance the FoM of a Si PV device ifexploitable engineering specification(s), such as the transfer functionor its associated FoM, could be identified, acquired, developed andsubsequently employed successfully in a SiPV engineered hybrid device orsystem that meets a prescribed and verifiable FoM that validates thedesired performance of the hybrid biophotonic device. However, theachievement of desired FoMs using hybrid device and system approaches isnot obvious to those skilled in the art of device design and developmentand empirical combinations of smart materials or components used in thedesign and manufacture hybrid device can oftentimes lead to device andsystem performances (i.e., FoM) inferior to nonhybrid device and systemcounterparts.

A preferred embodiment of the invention makes use of well-known designalgorithms, such as the Design of Experiment (DOE), among many othersknown and appreciated by those skilled in the art. DOE analysis is awidely used statistical modeling design tool reported in detailelsewhere (Montgomery, 1991). A unique advantage of DOE, particularly asapplied to complex adaptive systems, is its ability to elucidate, notonly the effect of the controlling or independent variables, but alsotheir oftentimes complex interactions.

The use of DOE analysis in combination with a novel MIMO/EC apparatuscan be used to identify, acquire or otherwise produce useful andexploitable engineering hybrid device and system specifications fromcomplex biological constructs in their isolated or natural state orenvironment, or mimics thereof. In particular, the combined use of DOEwith the MIMO/EC apparatus can provide a novel and powerful designheuristic to achieve desired engineering specifications ofnanoscale-based constructs via their identification and/or modificationfrom complex, adaptive systems, such as, viable organisms.

The use of the DOE-MIMO/EC apparatus in this embodiment is most usefulwhen it may be desirable to modify one or more properties of a complex,adaptive construct through the ‘forced adaptation’ of a modifiablebiological component of a viable, complex systems (such as bacteria).This produces the desired modification of a potentially useful propertyor characteristic of e.g. a nanoscale-based component that is useful toachieve a desired performance level (i.e. FoM) of a device or system inwhich that is not otherwise achievable by its nonhybrid.

In one embodiment of the invention by varying the environmentalconditions under which a biological component of, for example, a hybriddevice, is grown, a transfer function for that component can be altered.Using the MIMO/EC of this invention, a biological component may be forceadapted in such a manner as to affect a modification of a transferfunction that governs its outputs under given inputs. The desiredtransfer function can thus be engineered into a biological component,within bounds.

In one exemplary embodiment of the invention, the methods and equipmentof the invention are used to engineer an exemplary hybrid photoactivecomponent. That component combines a hitherto acceptable photoactivesemiconductor device with a biological mechanism that has extreme highphotoactive performance to achieve performance unprecedented in devicesof the type. This hybrid device, itself an exemplary and preferredembodiment of one aspect of this invention, uses a constituent of aphotosynthetic bacterium to enhance the response of a semiconductorphotoactive device across the intended spectrum of its use.

With the methods and equipment of this invention, chlorosomes of thethermophilic green photosynthetic bacterium Chloroflexus aurantiacus (C.aurantiacus) are successfully coupled to a photoactive semiconductordevice to derive enhanced performance across the relevant spectrum.

Here, using design of experiment (DOE) methodology, adaptive biologicalunits, such as cells, are force-adapted to achieve consistentperformance in the characteristics of interest. In this, a multipleinput-multiple output environment chamber (the above-mentioned MIMO/EC)affords the ability to force adapt the bacteria from which thesechlorosomes are gathered.

This embodiment is focused on exploiting biosystems at the nanoscale fortheir utility as functional ‘device’ components in a proposed biohybridmicrodevice. More specifically, a design feasibility study wasimplemented to evaluate the efficacy of a naturally occurring nanoscalebiophotonic, light adaptive ‘antenna’ structure (the chlorosome),isolated from C. aurantiacus. The overall objective was to assess itsutility as functional device component that would enhance the spectralperformance characteristics of well-characterized photonic devices,i.e., solid-state photovoltaic.

The chlorosomes are nanoscale, optical functional units (100×30×10 nm).They can transfer photonic energy at high quantum efficiencies (69-92%)and ultra-fast rates (picoseconds). They were fabricated into programmedarrays on solid substrates and fully characterized. These biologicalassemblies were subsequently integrated with the well-characterizedphotodetectors and evaluated for their potential to selectively enhanceperformance the spectral regions where the photodetectors are inherentlyinsensitive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual block diagram illustrating elements in the designand development of a device, in particular a hybrid device of biologicaland nonbiological content;

FIG. 2 is a conceptual flow chart of the design process for designing ahybrid device using a multiple input, multiple output environmentalchamber and employing a figure of merit to gauge the performance of abiological component;

FIG. 3. is an image of C. aurantiacus by a scanning electron microscope;

FIG. 4 is a cartoon schematic rendering of chlorosomes of C. aurantiacusin place in a cytoplasmic membrane;

FIG. 5 is a diagrammatic (cartoon) illustration of a chlorosome of thebacterium C. aurantiacus with its four major subunits (the chlorosomedesignated herein the RC⁺ chlorosome);

FIG. 6 is a diagrammatic (cartoon) illustration of the chlorosome of thebacterium C. aurantiacus of FIG. 5, but with two of its four subunits,the B808/866 protein light harvesting apparati and a reaction centerremoved (the chlorosome thus modified designated herein the RC⁻chlorosome);

FIG. 7 is a diagrammatic (cartoon) illustration of the chlorosome ofFIG. 6 with parts broken away for clarity showing contained rod-likestructures of Bchl c;

FIG. 8 is a functional block diagram in the form of a flow chart ofoptical interactions of the components of the chlorosome shown in FIG.5;

FIG. 9 is a plot of absorbent spectra data for a C. aurantiacuschlorosome;

FIG. 9A is a normalized absorbance spectra plot of the RC⁻ chlorosome;

FIG. 10 is a diagrammatic block diagram in the form of a flow chartindicating the optical interaction of the parts of the chlorosome ofFIG. 6;

FIG. 11 is a diagrammatic illustration, partly in section, of a hybridphotovoltaic device in accordance with the invention;

FIG. 12 is an enlarged fragmentary cross-sectional view along the line12-12 of FIG. 11 and shows the chlorosomes like that of FIG. 6 adherentto a transparent plate;

FIG. 13 a is a normal percentage probability plot and FIG. 13 b is theinteraction plot between temperature and percent volume for a design ofexperiments analysis where the output variable to be studied was theratio R1 of absorbance at 740 nm to absorbance at 808 nm;

FIG. 14 a is the normal percent probability plot and FIG. 14 b theinteraction plot between temperature and percent volume media to air fora design of experiments analysis where the output variable studied isthe ratio R2 of absorbance at 740 nm to absorbance at 366 nm;

FIG. 15 a is a plot of three replicates of a full spectra of C.aurantiacus at one dilution and FIG. 15 b plots full spectra ofabsorbance of C. aurantiacus at multiple concentrations;

FIG. 16 a is a plot of correlation between absorbance and cell count at650 nm wavelength for C. aurantiacus and FIG. 16 b is a plot ofcorrelation between absorbance and cell count at 740 nm wavelength;

FIG. 17 is a plot of correlation between absorbance and number of RC⁻chlorosomes of C. aurantiacus at 650 nm wavelength and a zoomed-in-plotof the first four data points in that correlation showing closelinearity between the two variables;

FIG. 18 is a plot of absorbance and emissions spectra of chlorosomes ofC. aurantiacus;

FIG. 19 is a plot of percent enhancement of a SiPV for percent coverageby chlorosomes of C. aurantiacus;

FIG. 20 is a functional block diagram that illustrates the use of afigure of merit in the development of a biological hybrid device withfeedback from the Figure of Merit determination through a DOE or thelike development program and feedback from the device performance;

FIG. 21 is in FIG. 21( a) a formula for the photonic figure of meritdevised for C. aurantiacus, in FIG. 21( b) a tabulation of the measuresgoing into that formula for seven specimens and in FIG. 21( c) a blockdiagram illustrating the interaction of the major contributing factorsto the figure of merit;

FIG. 22 is a diagrammatic illustration of a multiple input, multipleoutput environmental chamber having nine individual compartments;

FIG. 23 is a perspective view of an environmental chamber like thatdiagrammatically illustrated in FIG. 22;

FIG. 24 is a schematic illustration of a generalized hybrid device inaccordance with the invention;

FIG. 25 is a schematic illustration of a further generalized hybriddevice in accordance with the invention;

FIG. 26 is still another schematic illustration of another generalizedhybrid device in accordance with the invention;

FIG. 27 is a schematic, generalized, enlarged, fragmentary cross-sectionview of a biological component such as those employed in the devices ofFIGS. 24-26 and shows fluorescent units deployed in a matrix; and

FIG. 28 is a further schematic, generalized, enlarged cross-section viewof a biological component such as those employed in the devices of FIGS.24-26, and shows fluorescent units adherent to the surface of anonbiological photoactive element.

DETAILED DESCRIPTION

FIG. 24 is a schematic view of a generalized hybrid device 200. Thedevice 200 has a biological component 201 and a nonbiological component202. In broadest terms the biological component is located in energytransmitting relation to the nonbiological component 202. Activated, thebiological component transmits energy to the nonbiological componentcausing a change in state (such as an electrical characteristic change)of the nonbiological component. An energy transmitting intermediatelayer 203 may separate the components 202 and 203 or the components maybe in contact or spaced apart. The biological component may be made upof units of active biological material or materials (or analogs of suchmaterial or materials if available). And the units may be unitsharvested from a larger organism or organisms. The biological component201 may be comprised of a matrix containing the units. In the particularembodiments described here the biological component 201 fluoresces,exhibiting what is termed a Stokes shift, the emission of light at awavelength or wavelengths different from light illuminating andactivating the biological component 201. In the exemplary embodimentsdescribed here the nonbiological component is photoactive, that is tosay photovoltaic, photoconductive or photoemissive. The material ofcomponent 202 is typically a photoactive semiconductor. Light emittedfrom the biological component illuminating the photoactive nonbiologicalcomponent causes the photoactive nonbiological component to exhibit itscharacteristic photoactive behavior, i.e. developing a voltage,exhibiting a change in resistance or emitting electrons.

Conceivably the energy communicated from the biological component 201 tothe nonbiological component 202 could be transmitted by other thanlight. The transmission could be by the mechanism known as FRET(fluorescence resonant energy transfer) or by another mechanism wherebythe nonbiological component 202 is caused to react sympathetically tothe action of the activated biological component.

In the case of fluorescing biological component 201 and thephotoelectric nonbiological component 202, the intermediate layer 203could be a clear plastic or glass. Alternatively the component 201 maybe in contact with the component 202 or they may be spaced apart by forexample an air gap, a vacuum or a clear gas. If the biological component201 includes a matrix, that could be a clear plastic employed to supportactive biological units or a liquid such as water or a solventsupporting such units in a suspension such as a colloidal suspension.

Clearly what is important in these exemplary photoactive devices is thatthe components 201 and 202 be arranged in light communicating relationwith the component 202 located to receive light emitted by the component201. Also, when illuminated with light in one region of the spectrum at204, the component 201 emissions at 205 are to be in another, differentregion of the spectrum to which the component 202 is responsive (or hasheightened responsivity as compared to other regions of the spectrum towhich the component 202 is not responsive or has lower responsivity).That is to say, the characteristic photoactivity of the component 202results from (or is enhanced by) being illuminated by light in thatregion of the spectrum in which the component 201 emits light. Table Aidentifies exemplary biological organisms and the photoactive materialstherein capable of being used to form the component 201. Table B givesthe wavelengths of absorbed and emitted light of the photoactivematerials identified in Table A either in an appropriate solvent, in thecase of the chlorophylls, or standing alone in the cases of thecarotenoids and bilins. Table C lists photosensitive nonbiological orengineered elements capable of being used as the component 202. Table Dlists pairings of Table A and Table B elements with optical andphotoactive qualities qualifying them for use together in the device ofFIG. 24. The resultant device of FIG. 24 is one that exhibits thecharacteristic photoactivity of component 202 when illuminated withlight in the spectral region to which the component 202 is insensitiveor has less than desired sensitivity.

TABLE A Photosynthetic Pigments and Pigment Proteins Utilized in LightAntenna Structures from Various Biological Organisms* B B B Chl BOrganism Chl a Chl b Chl c Chl d Chl a Chl b c, d, e Chl g CarotenoidsBilins Purple + + + Bacteria Green Sulphur + + + Bacteria Green + + +Nonsulphur Bacteria Heliobacteria + + Cyanobacteria + + + + + + GreenAlgae + + + Diatoms + + + Brown Algae + + + Dinoflagellates + + +Cryptomonads + + + + Red Algae + + + + Plants (e.g. + + + maize) Chl a =Chlorophyll a; Chl b = Chlorophyll b; Chl c = Chlorophyll c; Chl ad =Chlorophyll d B Chl a = Bacterial Chlorophyll a; B Chl b = BacterialChlorophyll b; B Chl c = Bacterial Chlorophyll c; B Chl d = BacterialChlorophyll d. *Ref: Molecular Mechanisms of Photosynthesis, R.Blankenship, Blackwell Scientific, 2002.

TABLE B Spectroscopic Properties of Chlorophylls andBacteriochlorophylls in Vitro and of Pigments* Absorption (max) PigmentSolvent [nm] Emission† Chl a diethyl 662, 578, 430 670 ether Chl bdiethyl 644, 549, 455 652 ether Chl c pyridine 640, 593, 462 648 Chl ddiethyl 688, 447 696 ether B Chl a diethyl 773, 577, 358 781 ether B Chlb aceone 791, 592, 372 800 B Chl c diethyl 659, 429 667 ether B Chl ddiethyl 651, 423 659 ether B Chl e acetone 649, 462 657 B Chl g acetone762, 770 566, 405, 365 Carotenoids 400-500 550-675 (Range) Bilins(Range) 550-650 + {close oversize brace} 560-660 Biliproteins (Range)540-660 *Ref: Molecular Mechanisms of Photosynthesis, R. Blankenship,Blackwell Scientific, 2002. †Estimated.

TABLE C Materials Used for Photovoltaics (PVs) Eff* Engineered (%)Material approx Use* Spectral Sensitivity** Inorganic PV Materials*Amorphous Silicon 10 Most Common Form of Thin UV & IR Low; Highest(550-650) Film PV Cadmium Telluride 17 Sig & Growing Share of Thin UVLow; Highest @ IR ~900 nm [CdTE] Film PV Market Cu—In—Ga—Se 20 GrowingShare of Thin Film UV Low; Highest 600-800 nm Market Poly(micro) 20Widely USed Highest @~500-600 nm Crystalline Silicon Monocrystalline 25Most Common PV Material in UV Low; Vis Mod; High (750-1000) Silicon UseToday Indium Phosphide 22 In Lab R&D Only UV & IR Low; Highest @600-800nm Gallium Arsenide 25 Not Widely Used Yet UV Low; Highest @ 900-1200 nm(GaAs) GaAs/InP/Ge Hybrid 35 Lab R&D Only Organic PV Materials # DopedPentacene 4 to 8 Currenlty Under Peak QE Range: 400-650Commercialization Homojunction 2.4 36% @ 650 nm spiro-OMeTAD† 2.56Dye-Sensitized Solar Cell 38% @ 520 nm Technology MDMO-PPV-PCBM†† 2.550% @ 470 nm Cu 3.6 18% @ 620 nm phthalocyanine/C60 *Efficiencies fromcited reference: ‘Positioning-Thin Film Photovoltaics for Success’ ANanomarkets White Paper March 2008; www.nanomarkets.net **Estimated #From ref: Organic Photovoltaic Films, Materials Today, May 2002, p23†2,20 7,70-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,90-spirobifluorene(spiro-MeOTAD) ††MDMO-PPV (poly)[2-methyl,5-(3*,7** dimethyloctyloxy)]-p-phenylene vinylene): PCBM ([6,6]-phenyl C61 butyric acidmethyl ester)

TABLE D Biohybrid Combinations of Engineered PV Components andBioderived Light Antenna Components Relative Biophotonic ExemplaryBiophotonic Pairing Engineered Output Biohybrid Abs Bioderived EmissEngineered Abs Rel to Example nm Component B [max] Component A [nm] EngMat 1 470/740/750 Chlorosomes 772/805/808 Monocrystalline 750-1000Efficiency (from different silicon >25% species) 2 670 LHCI 730Monocrystalline 750-1000 Efficiency silicon >25% 3 470/670/740Chlorosome + LHCI 730 + 808 Monocrystalline 750-1000 Efficiencysilicon >25% 4 FMO Protein (BChl 785 Monocrystalline 750-1000 Efficiencya) silicon >25% 4 See below Phycobilisomes 537-660 Amorphous 550-650Efficiency (all) Silicon >10% (alone or in comb) 4a 565 (495)R-Phycoerythrin 575 Amorphous 550-650 Efficiency Silicon >10% 4b 545B-Phycoerythrin 575 Amorphous 550-650 Efficiency Silicon >10% 4c ~495(545)  Y-Phycoerythrin ~563 Amorphous 550-650 Efficiency Silicon >10% 4d615 C-Phycocyanin 647 Amorphous 550-650 Efficiency Silicon >10% 4e 617(555) R-Phycocyanin 637 Amorphous 550-650 Efficiency Silicon >10% 4f 652Allophycocyanin 660 Amorphous 550-650 Efficiency Silicon >10% 4g 566Phycoerythrin 566 617 Amorphous 550-650 Efficiency Silicon >10% 4h 575Phycoerythrocyanin 625 Amorphous 550-650 Efficiency Silicon >10% 5375/800/850 LH2 ~800 Indium 600-800 Efficiency Phosphide >22% 6470/740/750 Chlorosomes 772/805/808 Indium 600-800 EfficiencyPhosphide >22% 7 773, 577, 358 FMO Protein 785 Cu—In—Ga—Se 600-800Efficiency >20% 8 644, 549, 455 Chl b 648 Doped 650 EfficiencyPentacene >2.4% Homojunc Note: utilizing methods taught inspecification, biophotonic structures can be engineered to acquiredifferent biophotonic and other desired properties, e.g, absorbance andemission values, to obtain desired figures of merit that exceedengineered materials alone when put into exemplary pairings such asdepicted in above biohybrid examples

Table E relates species, light antenna structure, pigment and/or pigmentprotein with wavelengths of absorbed light and emitted light.

TABLE E Biophotonic Light Antenna Structures and Light AbsorptionEmission Values Pigment or Absorption Light Antenna Pigment-Protein(Max) Emission† Structure Complex [nm] [nm] Specie PERIPHERAL MEMBRANEPhycobilisomes Bilins 550-650 Cyanobacteria/Red [Bilins +phycocyanobilin Algae Biliproteins] [Bilins + phycoerythrobilinBiliproteins] [Bilins + Biliproteins 540-660 560-660 Biliproteins][Bilins + R-Phycoerythrin 565 (495) 575 Red Algae Biliproteins][Bilins + B-Phycoerythrin 545 575 Cyanobacteria/Red Biliproteins] Algae[Bilins + Y-Phycoerythrin ~495 (545)  ~563 Cyanobacteria Biliproteins][Bilins + C-Phycocyanin 615 647 Cyanobacteria/Red Biliproteins] Algae[Bilins + R-Phycocyanin 617 (555) 637 Biliproteins] [Bilins +Allophycocyanin 652 660 Cyanobacteria/Red Biliproteins] Algae [Bilins +Phycoerythrin 566 566 617 Biliproteins] [Bilins + Phycoerythrocyanin 575625 Green Sulphur Bacteria Biliproteins] Chlorosome B chl c, d, e 659,429/651, 423/ 808 Chloflexus Aurantiacus 649, 462 Chlorosome BChl c, a,Carot, Quin 470/750 772 & 805 Chlorobium tepidum FMO Protein B Chl a773, 577, 358 785 Fucus Serratus LH2 Complex B Chl a, Carotenoid 850,800, 750-470 890 Rhodopseudomonas Acidophila Green Sulphur BacteriaPeridinin- B Chl a & Carotenoid 660, 535, 437, 350 679, 675Dinoflagellates Chlorophyll Protein (PCP) LH2 Complex BChl/Carot/prot800-850 (375)   ~860 Purple Bacteria subunits INTEGRAL MEMBRANE FusedPS1 RC chlorophyll; β-carotene 430-660 ~700 Plants, Algae, ComplexesCyanobacteria Green Sulp Bact Bchl a; carotenes 450-850 ~860 GreenSulphur Bacteria RC Complex Heliobact Bact Bchl a; carotenes 450-850~860 Heliobacterial RC Complex Core CP43 & CP47 Chl a & œ-Carotene 660,450, 430 ~700 Plants, Algae, Complex PS2 Cyanobacteria LH1 Complex B Chla & œ-Carotene 875 (380) ~860 Anoxygenic Bacteria Accessory LHCIComplexes Chl a & Chl b 676, 470 715-735 Plant (Maize) of PS1 LHCII ofPS 2 Chl a & Chl b 675, 650 679 Plants & Algae LH2 Complex  832 (~375)800 Purple Bacteria PS 2 Chl a PSI & PSII 450 710 Algae (Diatom-PTricornutum) †estimates FMO = Fenna-Mathews-Olson LH1 = LightHarvesting 1 Complex; LH2 = Light Harvesting 2 Complex' PSI =Photosystem I; PSII = Photosytem II LHCI = Light Harvesting Complex I;LHCII = Light Harvesting Complex II; Bacterial RC = Bacterial ReactionCenter *References: Molecular Mechanisms of Photosynthesis, RBlankenship, Blackwell Scientific, 2002. Photosynthesis (Third Edition),David W Lawlor, BIOS Scientific Publishers, 2001. ProbingPhotosynthesis. Mechanisms Regulation & Adaptation, M Yanus, U Parthre,O Mohanty Eds), Taylor & Fancis, 2000. Chlorophylls and Bacteriophylls,B Grimm, RJ Porra, W Rudiger, H Scheer, Eds., Springer, 2006.

In each of the organisms identified in Table A, the photoactive proteinor protein pigment is present in an antenna structure. The methodologyfor isolating the unit that forms part of that antenna structurecontains the identified photoactive pigment or pigment protein is welldocumented in the literature. One or more of the publications listedbelow under Isolation, Separation and Harvesting Techniques for LightAntennas and Subunits sets forth a technique for isolating one or moreof the fluorescent units identified as useful in practicing anembodiment of the invention. Each publication listed is incorporatedherein by reference. Typically isolating the chosen structure involvesfirst isolating the antenna structure and then removing from thatantenna structure a reaction center (RC) that ordinarily absorbs lightat wavelengths emitted by the photoactive material identified in Table Ato produce protons. Other structure that does not contribute to theStokes shift phenomenon may be removed and discarded as well.

The antenna structures that contain the photoactive pigments and pigmentproteins used in the component 201 are nanoscale structures of variousshapes and may be directional in their light absorbing and emittingabilities, absorbing at one end and emitting at the other, say. In whichcase a majority to a totality of these structures are preferablysimilarly oriented within the component 201 so that the component 201 issimilarly directional in its light absorbing and emittingcharacteristic.

Orienting the units can be accomplished in a number of ways. In thespecific example that follows, because the chlorosomes of that example,when stripped of their reaction centers, have a hydrophilic portion orbase plate at the light emitting end, a hydrophilic glass slide was usedto support the chlorosomes, causing the hydrophilic portion of thechlorosomes to come to rest on the slide. Other techniques formanipulating nanoparticles such that their orientation can be assuredare addressed in the literature. See, for example, Lavan, D. et al.,“Approaches for biological and biomimetic energy conversion,” 5251-55,PNAS, vol. 103, no. 14, 2006; Morris, C. et al., “Self-Assembly forMicroscale and Nanoscale Packaging Steps Toward Self-Packaging,” 601-11,IEEE Transactions on Advanced Packaging, vol. 28, No. 4, 2005; Yoshino,M. et al., “Engineering surface and development of a new DNA micro arraychip,” 274-86, Wear 260, 2006; Kane, R. et al., “Patterning proteins andcells using soft lithography,” Biomaterials 20, 2363-76, 1999. Eachincorporated herein by reference.

It should be recognized that the structure of the device 200 of FIG. 24may be repeated many times throughout a bigger photoelectric device. Thedevice 200 or bigger photoelectric device may be encapsulated in such away as to permit the biological component 201 to be illuminated. Forexample by encapsulation in a clear plastic or glass.

FIG. 25 is a schematic view of a further hybrid photoelectric device210. A nonbiological component 212 and a biological component 215 havethe structure and characteristics of the nonbiological and biologicalcomponents 202 and 201 of the device 200 of FIG. 24. In a preferredphotoactive embodiment the nonbiological photoactive component 212receives the full spectrum of illuminating light at 213. The biologicalcomponent 215 receives the full spectrum of illuminating light at 216and emits light at 217. The nonbiological photoactive component isresponsive to (or has heightened responsivity to) light in a range ofwavelengths within the full spectrum of the illuminating light at 213 ascompared to other wavelengths, but is comparatively nonresponsive to (orless responsive to) light in another range of wavelengths within thefull spectrum of the illuminating light at 213. The biological component215 is responsive to light within the range of wavelengths to which thenonbiological component 212 is nonresponsive (or has low responsivity)and illuminates the nonbiological component with light at 217 that is atwavelengths among the wavelengths to which the nonbiological componentis responsive (or has comparatively higher responsivity). As a resultthe overall device of FIG. 25 acts as a photoelectric device responsiveto a wider spectral range than a device employing just the nonbiologicalcomponent 212 as the sole photoactive element. Again the biological andnonbiological components may be chosen and assembled in the same manneras in the device 200 of FIG. 24. Also multiple biological units ofdiffering characteristics may be employed in combination with thenonbiological component 212 to employ even more regions of the spectrumto which the nonbiological element 212 is not responsive or is lessresponsive.

As with the device of FIG. 24, the device 210 of FIG. 25 may be repeatedmany times throughout a larger overall device. The device 210 or largeroverall device may be encapsulated so long as the biological componentor components can be illuminated. Also, as is true of the device 200 ofFIG. 24, because of the minute nature of the biological antennastructures used in the preferred embodiments, the device can itself benanosized or by use of many multiples of the biological antennastructures can be much larger as fits a particular use.

A further embodiment of the invention is schematically illustrated inFIG. 26. The biological and nonbiological components of this device maybe as described with respect to the biological and nonbiologicalcomponents of the devices 200 and 210 of FIGS. 24 and 25. In a preferredphotoactive embodiment a device 220 includes a nonbiological orengineered photoactive component 222, a first photoactive biologicalcomponent 223 is responsive to light in a first region of the spectrumat 224 to emit light at 225 in a second region of the spectrum differentfrom the first region of the spectrum by which it is illuminated. Thesecond region of the spectrum includes wavelengths at which thenonbiological component 222 responds photoactively or has heightenedphotoactive responsivity as compared to other wavelengths. A secondphotoactive biological component 227 is of a photoactive biologicalmaterial different from the photoactive biological material of thecomponent 223.

In a first embodiment of the device 220, the component 227 is responsiveto light in a third region of the spectrum at 228 to emit light at 229in a region of the spectrum different from the third region of thespectrum by which it is illuminated. The light emitted by the secondbiological component 227 is in a region of the spectrum at which thenonbiological component is photoactively responsive or has heightenedphotoactive responsivity. That may be the same as the second region ofthe spectrum at which light is emitted by the biological component 223,or the light emitted by the second biological component 227 may be in aregion of the spectrum overlapping or different from the spectrum of thelight emanating from the first biological component 223. In thisembodiment of the device 220, then, the device is photoactive, or hasimproved photoactivity, in the manner of the photoactive nonbiologicalcomponent 222, but at several regions of the spectrum at which thecomponent 222 is not photoactively responsive or has lower than desiredphotoactive responsivity.

In a second embodiment of the device 220 of FIG. 26, the two photoactivebiological components 223 and 227 may be active in the same oroverlapping regions of the spectrum in the light illuminating them at224 and 228, but may emit light in differing regions of the spectrum atwhich the nonbiological component 222 is photoactive comparatively morehighly photoactive to take advantage of a photoactivity profile of thematerial of the component 222 that has several peaks at severaldifferent wavelengths, that is has heightened responsivity at variousdifferent wavelengths.

Additional biological components of characteristics different from thecomponent 223 and 227 may also be employed with the nonbiologicalcomponent 222 so as to extend the range of wavelengths impinged on thebiological components that activate the photoelectric characteristic ofthe nonbiological component 222 or to provide further illumination ofthe photoelectric element 222 in further regions of the spectrum wherethe particular photoelectric material has heightened responsivity. Againencasement of the device 220 is possible as long as the biologicalcomponents can be illuminated. This device too can be realized on thenanoscale or can be scaled up by the use of many of the active elementsmaking up the biological components 223 and 227. Also, as with thedevices 200 and 210 of the FIGS. 24 and 25, multiple devices 220 may beincorporated in a much larger overall device.

In each of the embodiments of FIGS. 24, 25 and 26 the photoactivenonbiological component may be a photovoltaic cell in which case avoltage V is developed across the output electrode pairs 206 and 207,218 and 219, and 230 and 231 in response to illumination of thenonbiological component by light in the proper range of wavelengths. Thefluorescent units making up the biological components 201, 215, 223 and227 of FIGS. 24-26 can be a mixture of such units derived from more thanone of the organisms of Table A (and such other organisms as may beidentified).

In addition to the photovoltaic materials listed, the nonbiologicalcomponent may be photoconductive materials or photoemissive materials.Photoconductive materials are materials that exhibit decreasedelectrical resistance when exposed to infrared rays, visible light orultraviolet light. Known photoconductive materials include cadmiumselenide, cadmium sulfide, germanium, lead sulfide, selenium, siliconand thallous sulfide. Photoemissive materials are substances that emitelectrons when exposed to infrared, visible light or ultravioletradiation. Known photoemissive materials are cesium, potassium, rubidiumand sodium. As in the case of choosing photovoltaic material for adevice as discussed, photoconductive materials or photoemissivematerials are chosen so that they are responsive (or have heightenedresponsivity) to illumination by light in the region of the spectrumemanating from the associated photoactive biological component.

FIG. 27 shows, in cross-section, a fragment of a biological component201, 215, 223 or 227 of FIG. 24, 25 or 26. Fluorescent units 250 areillustrated in a generalized, schematic fashion. The majority have theirlight emitting ends, which are dotted, facing right toward thephotoactive nonbiological member (not shown) and their light absorbentends, undotted, facing left to be illuminated. The units 250 aresuspended in a matrix 251 as discussed above. The units 250 arestructures removed from light harvesting antenna structures and containone or more of the pigments and pigment proteins identified in Table A.

FIG. 28 shows, in cross-section, a fragment of an alternate biologicalcomponent 201, 215, 223 or 227 of FIG. 24, 25 or 26 adherent to anonbiological photoactive component 201, 212 or 222 of FIG. 24, 25 or26. Fluorescent units 250, as described with respect to FIG. 27, areagain illustrated in a generalized, schematic fashion. Again themajority have their dotted light emitting ends facing right to thenonbiological photoactive element and their light absorbent ends,undotted, facing left to be illuminated. The units 250 are affixed to asurface of the nonbiological photoactive element adhesively or bylinking units known in the art as linkers, either represented in FIG. 28at 252.

The Table A listing of photoactive biological materials is notnecessarily exhaustive. Suitable photoactive biological materials otherthan those listed may be known or may be developed from species not yetknown.

Example

The following example sets forth the steps performed in successfullyconstructing a preferred embodiment of the invention in which thebiological fluorescent component uses the light antenna structure(chlorosome) of the bacterium Chloroflexus aurantiacus (C. aurantiacus).The detailed description of this one example will serve those skilled inthe art as a blueprint for the preparation of devices of the kinddescribed with respect to FIGS. 24, 25 and 26 using the furtherbiological and nonbiological component discussed above.

The bacteria, Chloroflexus aurantiacus (C. aurantiacus), strain J-10-f1,has the American Type Culture Collection (ATCC) designation number29366, having been deposited in July, 1976. The ATCC is located at 10801University Boulevard, Manassas, Va. 20110-2209 U.S.A. The C. aurantiacusbacteria is a green, nonsulfur, flexing/gliding, photosyntheticbacteria. It is thermophilic and can be found in hot springs up totemperatures of 70° C. in large mat-like layers. The layers, whenconcentrated enough, have an orange coloration.

A freeze fracture image of C. aurantiacus by scanning electronmicroscopy (SEM) was taken and is reproduced in FIG. 3. In the imagesmall ovals can be resolved. These are the cell's chlorosomes. At thissize scale reduction would require specialized EM or other imagingtechniques. Thus far, no high resolution structural information has beensuccessfully obtained on individual chlorosome structures, and as such acartoon schematic representation of the chlorosomes 100 in situ ispresented in FIG. 4. There, the chlorosomes 100 are depicted in place ina cytoplasmic membrane 95. A proposed model of a single chlorosome 100is shown enlarged in FIG. 5 in a 3-D cartoon. From the work ofBlankenship, et al., the chlorosome 100 is comprised of four majorsub-units: a Bchl c portion 101, a Bchl baseplate 102, B808/866 protein,supra molecular light harvesting complex or apparati 103, and a reactioncenter (RC) 104.

A chlorosome 110 of the C. aurantiacus bacterium is depicted in FIG. 6.It includes two major supra-molecular pigment-protein subunits. Theseare the bacteriochlorophyll (Bchl) c 101, and the supra-molecularbaseplate complex 102. In its form shown in FIG. 6 the C. aurantiacuschlorosome 100 is here designated RC⁺ (meaning with its RC 104 andB808/866 light harvesting apparati 103 in place). As depicted in FIG. 6at 110, stripped of its associated reaction center and B808/866supra-molecular complex 103, the chlorosome of C. aurantiacus isdesignated RC⁻ (meaning without the RC 104 and B808/866 light harvestingapparati 103). Each sub-unit of the chlorosome 100 illustrated in FIG. 5is composed of a large number of wavelength-specific light absorbing andtransducing molecules.

The first sub-unit involved in light transduction is a lipid sack 101containing bacteriochlorophyll (Bchl) c, which is organized in units ofapproximately 10,000 molecules that form rod-like structures 115 (FIG.7). As represented in the flow chart of FIG. 8 at 115, these moleculestransduce photonic energy associated with 740 to 750 nm light inapproximately 16 ps with very little loss. Photonic energy at 750 nm isthen transduced at 117 by the membrane of the baseplate 102, which iscomprised of approximately 500 molecules of Bchl a, to 795 nm to 800/810nm in 41-175 ps. The B808/866 complex 103 contains 10-20 Bchl amolecules, which absorb at 119 at 808 and 866 nm and transfer at 883 nmin approximately 250 ps. Finally, the last stage is where, at 121, aspecial pair of Bchl a molecules of the reaction center (RC) 104,convert the light energy into chemical (photochemistry) to emit photons.

FIG. 9 plots absorbance spectra data of isolated chlorosomes of C.aurantiacus noting peaks of interest. There, an absorbance peak at740-750 nm attributable to the Bchl c rods 113 appears. A peak at 795 nmassociated with the Bchl a baseplate is shown. In addition absorption oflight in the blue region by the cartenoids is evident and blue secondaryabsorbance peaks from the Bchl c and a (designated as Soret peaks)occur. A peak attributable to the monomeric form of Bchl c (like itsSoret) has a different absorbance wavelength peak than the oligomericform that comprises the rods 113 in the chlorosomes. Like the Bchl abaseplate peak, the Bchl c oligomeric c peak is in the near infrared(NIR).

Isolated RC⁻ chlorosomes in Tris buffer exhibit the absorbance peaks(solid line) shown in the normalized absorbance spectral plot of FIG.9A. Immobilizing the RC⁻ chlorosomes in PVAC polymer, however, destroyedthe chlorosomes as evidenced by the dashed line normalized absorbancespectrum plotted in FIG. 9A. This was true of other immobilizationattempts with other polymers.

Intact C. aurantiacus bacteria display a unique adaptive ability toreversibly and enzymatically assemble and disassemble the foregoingstructures to protect the organism from photo-induced damage. As isexpected, the spectral peaks of FIG. 9 are highly related to growthconditions of the whole cell C. aurantiacus bacteria. These are alsorelated to the isolation techniques that result in purified chlorosomes.An abbreviated form of the important basic mechanisms of energy transferthat occur between the molecules of the RC⁻ chlorosome are as depictedin FIG. 10.

The carotenoids have been shown to also transfer energy to the Bchl coligomeric rods as is true of the Soret band (a strong absorbance of achlorophyll in the blue region of light). However, there are subtledifferences in the Bchl c found in the chlorosomes. The Bchl c found inC. aurantiacus chlorosomes are self-assembled (from monomeric form) intooligomeric rods. This results in a shift of the normal Soret (and Q_(y))band into a redder form. The Bchl a found in the baseplate also has aSoret region in its photonic (blue) spectra. Carotenoids can begin toquench the structures and should be closely watched, as this would causethe device of this invention to operate at lower efficiencies.

In the exemplary embodiment of the invention that was successfully madeand tested, the RC⁻ chlorosomes were suspended in a liquid which wasthen applied to the hydrophobic surface of a borosilicate glass plate118 as shown in FIGS. 11 and 12. It is the bases 102 of the chlorosomes110 that adhere to the surface of the plate 118.

As shown in FIG. 11 the plate 118 is supported just above the surface ofa glass slide or substrate 120. An epoxy seal 121 is formed about theedges of the plate 118. On or closely spaced above the plate 118 acommercially available silicon photovoltaic cell is supported.Illumination of the chlorosomes and the photovoltaic cell 125 by an LED127 produces a voltage across the output of the photovoltaic cell 125 ascan be observed by a multimeter 129.

As shown in FIG. 18, when excited with 430 nm, 460 nm and 470 nm, whichis exactly where the silicon photovoltaic cell is less sensitive, theRC⁻ chlorosome emits at about 810 nm where the silicon photovoltaic cellis sensitive. There is, therefore, a spectral enhancement by theaddition of the biological component that is similar to that showngenerally in FIG. 18.

In an exemplary laboratory prototype of the device, the SiPV was anEdmond Optics NT53-371 photovoltaic cell. Slide 120 was a Fischermicrowells slide, part number 12-568-20 and the plate 118 was a Fischercover glass, part number 12-541A.

The microslide employed allowed for relatively straightforwardapplication of the chlorosomes. This particular slide has two frostedrings on its surface, one of which is indicated at 131 in FIG. 11. Thefrosted ring was just sufficiently high above the surface of the slide120 that a drop of the liquid suspension containing the chlorosomes wasretained. The cover glass 118 was rested on the ring 131 and when thesuspending liquid had evaporated leaving the chlorosomes adherent to thehydrophobic borosilicate cover glass surface as shown, the epoxy seal121 was applied. The microwells slide was useful in another respect.Having two of the frosted rings 131, it permitted for the side-by-sideconstruction as illustrated in FIG. 11 and a control. The control couldbe an identical silicon photovoltaic cell illuminated through the slide120 and a further glass 118 but absent the chlorosomes, or the controlcould be as illustrated in FIG. 11 but having the RC⁺ chlorosomesentrapped.

In the arrangement of FIG. 11, the RC⁻ chlorosomes and the lightreceiving surface of the photovoltaic cells were no more than amillimeter apart. As indicated in FIG. 11, the construction of theoff-the-shelf photovoltaic cell placed the light receiving surface 133of the silicon semiconductor in a metal housing or can 135 to be exposedthrough a glass closure 137.

Characteristics of the biological component of the hybrid device of FIG.11 are set forth in Table 1.

TABLE 1 Schematic Pictures of chlorosomes + Si PV ChlorosomeCharacteristics Size: 100 × 30 × 10 nm Approx Rh: 33 nm (calculated) 41nm (DLS) Energy Transfer: Strokes Shift: 470-800/810 nm Δλ: 320 nm QE:69-92% QE Delay Time: 50 ps−1 ns Orientation Yes Control: Number of 4 ×10⁷-8 × 10⁹ chlorosomes particles: Number of 4 × 10¹⁵-810¹⁷ molecules:

EXPERIMENTAL

Materials and Methods

First, the biological component (the RC chlorosomes), as well ascontrols, had to be isolated or purchased. Next, several types ofcharacterization had to be performed (and developed in some cases) sothat the device fabrication could be accomplished. These involved manysteps (and iterations) until sufficient materials were readily available(in the correct form) for use in the hybrid device configuration.

C. aurantiacus cells were grown in ‘D’ media, under 6000 lux 50° C. in aone liter bottle (FIG. 3.2). The ‘D’ mixture is as follows (allchemicals from Sigma): A mixture of 50.0 ml of the medium D stock isadded to distilled water with 2.0 gm Difco Yeast Extract, 1.0 gmGlycylgylcine (freebase) adjusting the pH to 8.2. This mixture is thenautoclaved for 0.5 hr at 450° C. The medium D stock is prepared bymixing 40.0 ml of Nitch's Solution to 80.0 ml of the FeCl₃ solution in3.5 l of distilled water with the following traces: 8.0 gmNitrilotriacetic acid, 4.8 gm of CaSO₄.2H₂O, 8.0 gm MgSO₄.7H₂O, 0.64 gmNaCl, 8.24 gm KNO₃, 55.12 gm NaNO₃, and 8.88 gm Na₂HPO₄. The Nitch'ssolution is made by placing 0.5 ml concentrated H₂SO₄, 2.28 gmMnSO₄.H₂O, 0.5 gm ZnSO₄.7H₂O, 0.50 gm H₃BO₃, 0.025 gm CuSO₄.7H₂O, 0.025gm Na₂MoO₄.2H₂O, and 0.045 gm CoCl₂.6H₂O into 1 liter of distilledwater. This should be stored refrigerated. The FeCl₃ solution isprepared by adding 0.2905 gm of FeCl₃ (or 0.4842 gm FeCl₃.6H₂O) to 1liter distilled water and should also be refrigerated.

RC⁻ chlorosome isolation (Gerola, 1986) starts with cells concentrated(600 ml) by centrifugation at 3,600×g for 60 min. 2M NaSCN with 10 mMascorbic acid in 10 mM Pi buffer (6.5 ml monobasic: 43.5 ml dibasicphosphate buffer per liter) was added to the weighed pellet in 4 ml/gmamounts. Cells were homogenized 10× in a cell disruptor/homogenizer(Fisher Scientific). Disruption of cells was performed by (one) pass ina 4° C. stored French Press (ThermoSpectronic) cell with 20,000 psi.DNAse I (Sigma) was added and the solution was incubated for 30 min atroom temperature. The solution was passed through the cell two moretimes.

Cell debris was removed by pelleting at 3,600×g for 1 hr. A continuoussucrose gradient was established by placing 2.0 ml of a 40% sucrose inthe NaSCN buffer in a tube and layering on 3.0 ml of a 10% sucrosesolution. The tubes were placed, horizontally, into a dark, 5° C.storage until use (48 hrs later). The addition of 1.2 ml chlorosomesolution to the top and ultracentifugation at 144,000×g for 18 hrs wasstarted. Bands were collected by removal of the top band (by color),then removal by 1 ml at a time until the pellet was reached. The pelletwas collected by addition of 1 ml to the tube and slight sonication tohomogenize the pellet).

After isolation of the RC⁻ chlorosomes from C. aurantiacus whole cells,the chlorosomes were (at various dilutions into Tris buffer) tested asin the above methods. This was performed in order to assess qualitycontrol by comparing spectral data (on absorbance) and relative output(emission).

Surface effects (of the substrates) were tested by contact anglegoniometry. This required a flat substrate (of sufficient surface area)to be placed on a Rame-Hart NRL Contact Angle Goniometer and test thecontact angle with solution of known surface energies; Solution dropletformation was done with a syringe and about 100 μl droplet. Images weretaken with the instruments CCD and using the RHI Imaging 2001 softwareto capture the digital pictures. Analysis can be done with the software.As well, as images were printed out and results were manually verified.

Another technique utilized the evaporation procedure as well as anaqueous method to allow incorporation of the chlorosomes onto a glasssurface. Both techniques start with taking 0.5 μl of a knownconcentration of chlorosomes and placing it onto a borosilicate glasscoverslip (Fisher Scientific). In the evaporation method, evaporation,under vacuum, is performed overnight and then the sample is sealed ontoa fluorescent antibody microslide (Fisher Scientific). In the physicaladsorption method, the slide is prepared in the aqueous phase andinverted during sealing, thus allowing for ensuring a hydrated sample aswell as diffusion of the chlorosomes onto the surface of the hydrophobicglass. Samples were also studied under laser scanning confocalmicroscopy (instrument from LEICA) to investigate orientation andfunction (stability) was observed with absorbance spectroscopy of thesample afterwards.

The engineering photonic devices had to be characterized. Using amodified NIST approach to calibrate the detectors, a system to developsensitivity curves (to wavelength) was established. Each device wascalibrated under similar conditions and intensities were varied todemonstrate intensity changes (if present) in the device. Finally,devices that were to be enhanced had to be selected. Knownnonlinearities in traditional devices, such as the silicon PV's (orsolar cells) were selected as optimal devices for enhancement.

These devices were stimulated by white light filtered with interferencefilters to provide wavelength control from blue to NIR. Intensity wasadjusted and matched using a radiometer from International Light(IL-1700). Changing the intensity from 0.01 to 70 lux caused a dramaticshift in the blue region by use of NDF's on an optical table (EdmundOptical Division).

The counting and size information gathering was accomplished by severalhigh-resolution microscopy techniques. Transmission Electron Microscopy(TEM) was performed by taking isolated chlorosomes and evaporating a 0.5μl drop onto a bacitracin treated formvar coated grid (300 mesh).Negative stains of uranyl acetate were used to enhance the images.Images were taken at the Life Science EM Facility at 25,000×magnification. Images were saved in jpeg format, inserted into MATLABand data (size and counts) were taken. Calculations were then scaled topredict how many chlorosomes were in a 1 ml sample for each of threedilutions. Absorbance spectroscopy of these dilutions was also performedto correlate absorbance spectra to count for the given population usinga Beckman DU-65 photo spectrometer (technique mentioned later).

A final method was used to gather most of the counting data, namely,Field Emission Scanning Electron Microscopy (FESEM) at the Center forSolid State Electronics Research Center at Arizona State University on aHitachi 4700 FESEM. Again, a hemocytometer technique was employed as aninitial method that could be correlated to the others. Another techniqueused computer aided image processing to allow the chlorosomes surface tobe assigned a ‘1’ or ‘white’ pixel value and the background a ‘0’ or‘black’. Accounting for surface area (number of pixels) per chlorosome,histograms were made and counts were calculated via computer. The finaltechnique was a modified ASTM method in which the surface is transversedfrom left to right, and top to bottom, counting chlorosomes until 100 isreached. Then the number of pictures required to reach ˜100 chlorosomes,the surface area of each picture, etc are accounted for and a final #chlorosomes/ml is calculated. Here, five concentrations (plus adistilled water control) were imaged using all three techniques andcounts were correlated to ABS spectra as well to aid in futurecalculations or determinations. The stubs were prepared by evaporating100 μl of the dilution onto a hydrophobic borosilicate glass disk,attaching the disk to a stub via tape and carbon coating the samples fora period of 10 minutes. The chlorosomes were diluted with Tris buffer atpH 8.0 and 10 mM NaCl, by addition of 0.788 gm Trizma HCl into 500 ml ofDI water, under constant stirring. Meanwhile, add 0.605 gm of TrizmaBase was added into 500 ml of DI water under constant stirring. Bothsolutions were mixed together and 0.9 gm NaCl was added while mixturewas stirred thus making 1 liter of 10 mM Trizma buffer, pH 8.0 with 20mM NaCl.

Another imaging technique, namely Atomic Force Microscopy (AFM) wasperformed by evaporating a 100 μl sample of chlorosomes (overnight indesiccant jar) onto a standard borosilicate coverglass. A DigitalInstruments' Nanoscope III Multimode AFM was used in Tapping Mode(TMAFM) to image the chlorosomes at various dilutions. Again, thedilutions' absorbance spectra were taken prior to imaging. Prior torunning the AFM experiments, a known liquid volume (400 μl) was takenfrom solution containing RC⁻ chlorosomes in DI water previouslycharacterized via absorbance spectra (ABS=0.01 @740 nm) and wasevaporated onto a clean, optically clear glass disk with known surfacearea (113.1 mm²). The disks were made hydrophobic to enhance RC⁻attachment and orientation due to theoretical studies performed by usinga molecular modeling algorithm (Chou, 1977) that suggested that thebaseplate region attached to the reaction center may be hydrophobic innature. Tapping mode AFM experiments were conducted utilizing a smallscan head (D head) to scan 1 μm² surface areas on both the control disks(no RC⁻ chlorosomes deposited) and test disks (RC⁻ chlorosomesdeposited).

Ranges of dilutions were made by serial dilution of the stock chlorosomesample. Each dilution was placed into a standard cuvette (using a blankof Tris buffer) and full (400-900 nm) absorbance readings were gathered(via an RS232C port) onto computer and analyzed and plotted in MATLAB.At this point, selection of a non-pigment wavelength (650 nm in the caseof the chlorosomes) was made to use in correlating absorbance to theprevious counts made on each dilution and then plotted. This wavelengthwas selected for its non-photosynthetic (non-optically active)properties and consistent nature between different growth conditionsduring the counting experiments. Hence, a calibration curve was madebetween counting and absorbance for a series of dilutions ofchlorosomes.

The TEM images were placed into the Image Processing Toolbox for MATLABfor sizing measurements and calculations processing. The scalebar wasmeasured (in the number of pixels across it to length) and thencorrelated to the size of the bar so a conversion could be made forlength and width of chlorosomes. The command ‘ginput’ was used to grabthe distal ends of the chlorosomes and utilizing the PythagoreanTheorem: a²+b²=c², measurements of length and width were made byselecting random chlorosomes and measuring 5 per image. 25 chlorosomesfrom each image were selected and measured to ensure statisticaldistributions could be made. Counts (per μm²) at this point were alsomade and calculations were made to correlate to a count per ml of eachdilution and then related to the corresponding absorbance spectra.

In the AFM and FESEM studied, the images were taken and saved in jpegformat for processing in MATLAB as was done in the TEM images. Size wasverified but in these techniques, counting was the main objective. Thesame process of taking the counts in an area and re-calculating what thecount per ml was performed on many dilutions to enable a more accuratecount (and correlation to absorbance data).

The same samples were sent to Protein Solutions Inc. DLS was run on thesamples. Later (after purchase of a DLS system) 20.0 μl of each samplewas injected via a gas-tight syringe into the quartz cuvette andreadings were taken at 2 Acq/sec. Data filtering was performed tominimize dust events but capture the quickly diffusing small particles.The Dynamics V6 software developed the autocorrelation curves andproduced the polydisperse plots of R_(h) versus % mass for each sample.

During the AFM studies, the hydrophobicity of the baseplate was studiedby utilizing differently treated coverglass in LSC. Untreated coverglassremained very hydrophobic, with a critical surface tension around 12dynes/cm, a surface tension of 32 dynes/cm, and a contact angle (for DIwater) of 41°. A heat treatment (450° C. for 4 hours) allowed for thecoverglass to pass through the glass-transition (T_(g)) temperature anddelivers the surface into a hydrophilic state (surface tension close to12 dynes/cm and a contact angle of ≦1° for DI water). The samples wereplaced onto the surfaces (in a laminar flow hood to reducecontamination) and evaporated under vacuum over night. Imaging wasperformed within 36 hours of evaporation so that the chlorosomes wouldnot swell (degrade). Images were taken and stored as jpeg format filesand processed in MATLAB as with the other imaging techniques. Unusualformations or interactions at the surface were also imaged in thepictures. Placement of the concentrations required to make certainpercent coverages into the microwells were done with an incubation timenecessary for physical adsorption. The time was a predicted time basedupon diffusion coefficient of the chlorosomes (as measured by DLS) andthe path length. The final, assembled coverglass and microwells weresealed with a two-part epoxy and allowed to cure overnight.

The first stability test for the isolated chlorosomes tested storageunder two conditions. A ‘fresh’ sample was maintained for use in 7° C.freezer and a long-term (or later called ‘frozen’) sample was placed inliquid nitrogen (LN₂). Initial degradation was noted in the samples andcan be clearly seen (at the monomeric 670 nm absorbance peak) in theabsorbance spectra of the ‘fresh’ sample. Emission spectra were evengathered to see if a decrease in emission occurred.

In intensity related photodegradation, concentrations were matchedbetween all samples (six different intensities were investigated) byabsorbance readings. Therefore, a series of experiments were designedand run with chlorosomes, with and without reaction centers, insolution, to see this effect. Samples were diluted to 1:100 of theoriginal stock into Tris buffer. 2 ml each were separated out for 6different light conditions. Light intensity was varied by the use offilters, no filter, or no light such that % Transmissions were 0% T, 14%T, 36% T, 53% T, 68% T, and 100% T and measured (photometrically). Thelight source was a standard 100-watt white light bulb. Degradation wasrecorded at times when 5, 10, and 15% degradation was noted. Degradationwas quantified by noting a percent decrease in the 740 nm absorbance.The samples were continuously illuminated and at specific timeintervals, absorbance readings were taken. Degradation of the 740 Bchl cQ_(y) band was measured by (1) peak height from start to finish and by(2) integration of the area under the Q_(y) band. Times were marked when5, 10, and 15% degradation of the peak were attained. A control sample(buffer) was also held under the same illumination and used as the blankin the photospectrometer.

Next, in intensity related to concentration photodegradationexperiments, various concentrations of chlorosomes (in 2 ml) weredegraded by a similar white light (at fixed intensity). From these setsof experiments minimum photostress terms were calculated to determine a0% degradation intensity (and time). Again, the 740 nm peak heightprovided a measure (by absorbance spectra) of photodegradation overtime.

Another mode of destruction of the photo-stability of the chlorosomescould be simple denaturation (by acidicity) by the buffer. Therefore,buffers (with a varying pH) were made from pH 2.0 to 12.0 and 1 ml ofeach was added to 1 ml of a chlorosome stock solution. Absorbancespectra as well as R_(h) were measured for each sample. The R_(h) wasmeasured by testing 20 μl of the sample in the DLS system.

Heat (or temperature) induced photodegradation or denaturation was alsoexplored and tested. Starting at room temperature, a water bath holdinga vial of chlorosomes was brought to near boiling over a period ofhours. During the experiment, absorbance readings were taken at aboutevery 5-10° C. and degradation was calculated as mentioned previously.

Another mode of destruction of the photo-stability was tested byincreasing the concentration of the chlorosomes, in solution to see ifconcentration aggregation could be attained. This was accomplished byuse of concentration filters and measured by R_(h). 15 ml of sample wasconcentrated down to differing volumes and the filtrate (buffer) wasremoved leaving a more concentrated sample. Then 20 μl of sample wasremoved for DLS measurements after absorbance spectra were taken toensure viable sample and perform chlorosome counting.

A final experiment to show another mode of destruction ofphoto-stability was the addition of a competitor (for absorbance of bluelight). Carotenoid solutions from the isolation procedure werereintroduced into the chlorosome sample (by dilution) and emissionmeasurements were taken. Side control experiments were performed byaddition of buffer alone. Stimulation was made by the RF-1501 Shimadzuspectrofluorometer and emission was measured on a photodiode afterpassage through an 800 nm interference filter (so that scatter andexcitation energies could be removed). This also allowed for ratios ofthe Bchl c to a, Soret, and carotenoid peak to be calculated andcompared for potential enhancement calculations for the hybrid wellexperiments.

The initial step in manufacture of the hybrid wells is the chlorosomes(or controls) themselves. First the isolated solution of chlorosomes hadto be measured in order to determine the actual number of chlorosomes(per ml) in the solution. For the controls, this was done by number ofmolecules based upon molecular weight (fluorescein) or counts suppliedby manufacturers (unlabeled and labeled particles). Next, calculations(and dilutions) had to be made in order to develop a varying percentcoverage. When all coverages (and dilutions) were made, the procedurewas the same. Place 20 μl of sample onto a hydrophobic coverglass andincubate in the laminar flow hood, in the dark, for at least 10 minutes.This gives the chlorosomes (or controls) enough time to physicallyadsorb onto the borosilicate glass surface. Next, invert the coverglassand place on top of the microslide holder centered on the frosted ring(1 cm in diameter). Sealing is performed by use of a 2-part (opticalgrade) epoxy. The samples are then placed in a microslide holder andstored over night (at least 24 hours) in the dark at room temperature.Further storage should be done at 5° C. in the dark.

The biophotonic hybrid device had to then be assembled, using thevarious interfacing techniques to integrate the chlorosomes (andcontrols), in a controlled, patterned array with the silicon (Si)photovoltaic (PV) photocell. Once fabricated, the device parameters orspecifications had to be tested. These include: maximum output,time-response (or rise time), spectral sensitivity, intensitysensitivity, temperature sensitivity, and device lifetime.

The device was fabricated by utilizing physical adsorptionimmobilization to interface chlorosomes (on a glass substrate/microslidewith well) to the Si PV photocell. The components were interfaced(mechanically) by a self-built optical chamber made from acrylic sheet.The microslide port was milled into one piece, holes were drilled forthe fiber optic bundle and the Si PV detector. Accessory ports/chamberswere made to fit 25 mm filters such as additive (or subtractive) and NDFfor wavelength and intensity control, respectively. The whole apparatuswas black felted to reduce external light leakage. Power was suppliedusing a standard variable power supply (for the LED) and the Si PV wasmonitored utilizing a digital multimeter (DMM).

In this arrangement, device parameters such as maximum output,time-response (or rise time), spectral sensitivity, intensitysensitivity, temperature sensitivity, and device lifetime were tested.Maximum output was monitored by allowing the device sufficient time togo from 0 millivolts (mV) to maximum for that particular LED intensity.The difference was recorded and compared to when no sample isintroduced. This ratio was defined as normalized relative output in thefollowing sections. Response time is defined as the time that requiredgoing from 0 to 90% of the final value during a switching on stage.

This was performed by timing a device versus the standard Si PV detector(no device attached). Spectral sensitivity was performed by replacingthe LED with various colored LED's that covered the visible spectrum aswell as into the near infrared (NIR). Voltages were recorded, andnormalized relative outputs were made on the final device. All deviceswere tested using 470 nm, 735 nm, 880 nm, and white LED's (fullspectra). Intensity sensitivity was verified using the blue (470 nm) LEDsince this was the wavelength of choice for enhancement.

Stability was verified by absorbance spectroscopy (400-900 nm) anddegradation was recorded. Temperature of operation was also investigatedand degradation was also monitored so that an operational range oftemperatures could be established. In these experiments, data was alsoobtained to establish device lifetimes under such ‘operational’conditions. The lifetime was determined by seeing what conditions led todevice degradation and the time required to reach that point.

The devices (ranging from low to high percent coverages) were testedunder LED illumination and ratios were made to the same detector underthe same illumination (minus the hybrid wells) and percentages have beencalculated. This percent enhancement signifies when a hybrid well deviceincreases the measured output (and by how much percent) over thestand-alone configuration. The rise time (the time it takes to get from10% to 90% final voltage) was measured and compared between the hybridwell devices to the stand-alone detector. This was accomplished with astopwatch and DMM. White light LED (visible light) stimulation of aseries of percent coverages have been conducted and compared tomonochromatic results. White LED's were implemented into the deviceapparatus and run at a few intensities and on Si PV as well as Si TP.Device enhancement was not further enhanced by the addition of the fullspectra light, in fact, red band quenching might have been recorded asnoted by others (Klar, 2000) in other systems and setups. Usingmonochromatic light as the stimulation source intensities were run atdifferent levels sufficient for device detection but lower thansaturation (of device or hybrid component). Again, full range of percentcoverages were evaluated and replicates run. Again, the detector'sresponse (without the hybrid layer) was used as a point of reference indetermining percent enhancement.

Other tests included data gathered from solution effect studies only.Temperature effects were determined by the previous experiment in whichthe chlorosomes' photostability to temperature changes was determined.Being in a bulk system in a water bath controlled environment fitted thedesign parameters of the hybrid well experiments and throughout testing,no experiments were conducted outside the 25-100° C. range. A series ofhybrid devices were constructed and tested (positively) over a largeperiod of time (and intensities). Further experimentation was conductedon these samples throughout the research endeavor until no (positive)responses were seen. Afterwards, the absorbance spectra of a few highpercent coverages were measured using a home-built slide holder in theDU-65 Beckman Photospectrometer in order to check the status(photostability) of the chlorosomes.

Forced Adaptation

Inconsistent results initially plagued experiments leading to thedevelopment of the hybrid device of the invention. As noted, C.aurantiacus is self-adapting. This meant that chlorosomes taken from thesame growth of cells could not be relied upon to behave consistently.

To overcome this lack of consistency force-adapted C. aurantiacus wasdeveloped having the performance desired. To this end, and because ofthe number of environmental variables involved in the growth of thecells and their substituent chlorosomes, a design of experiment (DoE)technique was employed to arrive at chlorosomes that performed well andconsistently.

In relation to biophotonic device design, there are many pertinentissues in each stage of the design. Variables encountered throughout theentire process of making the hybrid photovoltaic device that are capableof affecting results are set out in Table 2. The design of the productstage (as tested by validation techniques) requires that the device betested via an appropriate light source type and wavelength (such as a470 nm LED) or a incandescent light bulb with correct interferencefilter (470 nm), and can be projected to the surface of the device withor without the aid of light pipes such as waveguides and/or fiberoptics. The intensity that the device is stimulated with must also be ofappropriate intensity as controlled by the voltage applied to the source(LED for example), a neutral density filter (NDF), or other means.Stimulation time must also be accounted for since the time ofstimulation and intensity will correlate to a certain photostress thatthe device can handle before irreversible damage is done to thebiohybrid layer. A controlled environment (for validation purposes) isalso necessary (a dark room or constant intensity area), as well asselection of an appropriate measuring device, such as a high impedancedigital multimeter (DMM) for photovoltaic devices for example.

Before the device can be tested however, materials must beacquired/produced and synthesized. These stages involve: growth of thebacteria and alteration (if any) of the chlorosomes. In this example,synthesis is governed by production in that changes in the chlorosomescan be induced by the growth period factors. Some of these factorsinclude: intensity of light source, light type and wavelength(incandescent, LED, fluorescent); media (pH, temperature, components orstrength); number of days allowed for growth (before isolation or mediaexchange); bottle-fill volume; and temperature. Some of these factorsdirectly influence important design characteristics such as Figure ofMerit (FoM), chlorosome size, photostability, and indirectly quenchers,to list a few.

Processing of the chlorosome requires isolation of the chlorosomes fromthe whole cell walls. This is done using a procedure well documented inthe literature although certain factors do arise in the process. Thereare different procedures used to isolate chlorosomes without thereaction centers (RC⁻) versus those with (RC⁺). The solvents, agents,and buffer types used in the procedure are also very important andfactors such as (the type, molarity, ionic strength, pH, and strength)all come into play. These factors will affect the state of aggregationand purity (and successful use) of the isolated chlorosomes.

Manufacture of the chlorosome layer is the step whereby means ofimmobilization (namely physical adsorption) a monolayer (or percentthereof) is deposited onto the surface of a substrate (borosilicateglass). Important factors for successful devices include: thefabrication conditions (temperature, incubation time, Light ON/OFF, andin the laminar flow hood); sealing method; concentration, volume, and %coverage (and hence interparticle distances); droplet placement (on thecoverslip or in the well); and coverslip hydrophobicity, which allrelate to chlorosome orientation (facing Si PV or LED).

Again, product final assembly is addressed above. However, other issuespertaining to lifetime of device and/or other issues such as postfabrication storage include factors of temperature, light intensity (andquality—i.e. wavelength) and # days, to name but a few.

TABLE 2 WELL ISSUES Growth Isolation Sample Fab Sample Run IntensityProcedure Fab conditions Light Source type Temperature LED Incubationtime Light bulb Light ON/OFF W/wout F.O. laminar hood Media BufferBuffer Light Intensity Type Type V_(applied) Molarity Molarity NDF usedIonic Strength Ionic Strength Measure tech. pH pH Stim. Time TemperatureTemperature pH Aggregated? Sealing method Light wavelength V_(applied)LED Light type Type (RC ±) Post fab storage Holder IncandescentTemperature Sample holder LED Dark LED + NDF Fluorescent # days SiPV +LPF Days of growth Purity % coverage Intensity control Bottle VolumeVolume Detector Temperature Droplet placed DMM used On coverslip 9 V(new) In Well High Imped. Wavelength Coverslip Orientationhydrophobicity Facing SiPV Facing LED Concentration Red LPF used VoltageApplied NDF used Room lights ON/OFF Stimulation time

In one stage of the development of the preferred exemplary proceduresdescribed in the above example, a multiple input, multiple outputenvironmental chamber 150 (MIMO/EC) was constructed as diagrammed inFIG. 22.

Nine compartments 155 through 163 were provided. Light intensityincreased from left to right across the three columns of compartmentsand temperature increased from bottom to top across the three rows ofcompartments. Within the compartments three differing volumes of mediawere contained. Consequently, 27 combinations of variables were able tobe tested. FIG. 23 illustrates an environmental chamber of this kind. Onits door 170 multiple shelves 172 are supported and have openings toretain culture-containing rest tubes or containers. Vertical dividers174 separate the compartments 155-163. Horizontal dividers 176 separatethe compartments vertically. Light bulbs, one of which is shown at 177provide illumination. A series of fans 179 regulate temperature.

Ordinarily in biology research is conducted on the OFAT, one factor at atime method. Here, the DOE approach permitted the three factors, lightintensity, temperature and media to air volume ratio to be tested atthree levels with three replicates and an additional three centerpointsand a total of 27 experiments (23×3+3=27). The DOE technique allows forcorrelation of data statistically easier than OFAT or best-guessapproaches. It reduces the total number of experiments, allows for agood, thorough experimental design. It allows for error to be quantifiedand it can distinguish if factors have any to no effect or ifinteraction among factors occurs. Here, the response, the output understudy, was concentration (by absorbent spectroscopy) after three days'growth.

Example

A factorial design was chosen to quantify the relative importance ofinteraction between light intensity, temperature, and volume of media.The approach used was Design of Experiments (DOE). This method allowsfor data to be gathered in a way to avoid error by establishing anexperiment protocol and quantify error in a mathematical way. Theregression method that was used was the analysis of variance (ANOVA)technique. This tool (DOE) allows for data to be gathered at normalconditions (centerpoint) and at extremes (above and below thecenterpoint). Analysis is based on quantifying effect and probability ofeffect of a factor or interaction on the output variable.

Cell Culture Stock

The cell culture stock was prepared for testing as in [1] and theMIMO/EC DOE culture incubation apparatus was also used. The data wasgathered from nine strands that all came from a centerpoint grown stock(cultured at the centerpoint for 14 days). The data was gathered(randomly) at the end of a three-day growth cycle period and placed intothe Stat-Ease™ software for analysis. Three replicates at each cornerwere taken as well as five centerpoint readings.

Pigment Protein Content Determination

The pigment protein content was deduced by taking absorbance spectrafrom 650 nm to 900 nm on each sample. This was done with a Beckman DU-65photospectrometer. Then a ratio (R₁) was calculated by dividing theabsorbance at 740 nm by that at 808 nm. Then another ratio (R₂) wascalculated with the 740 over 866 nm peak absorbance readings. In thisexperiment, pigment protein content was desired to see an increase(larger chlorosomes).

Statistical Analysis Approach

The DOE approach used involves seven steps in order to perform theexperiment. The first step involves defining the problem statement. Hereit was desired to investigate which factors could increase the pigmentprotein content of the chlorosomes. Next, the choice of the factors,which may influence pigment protein content, had to be chosen. Also, thelevels of these factors had to be established. The factors that werechosen, and their levels can be found in Table 3. below.

TABLE 3 Low, Centerpoint, and High Factor Levels for DOE ExperimentFactor Low (−) Center High (+) A = Temp 36° C. 48° C. 60° C. B =Intensity 50 lumen 270 lumen 490 lumen C = Media 5 ml 7.5 ml 10 ml

The next step is to identify the output variable(s) to be studied. Sincethe change in pigment protein content was desired to be analyzed, theratios of the 740 to 808 and 740 to 866 nm peak absorbances were chosen.The ratios were designated with a R₁ for the 740/808 and a R₂ for the740/866 ratio. Since the choice of factors and levels were as stated, a23 factorial approach was chosen. In this approach, three replicates andfive centerpoints were chosen also. The experiment was run at the end ofa three day growth period and data was gathered in a random fashion.Since replicates were used the data analysis will not includedetermination normal % distribution plot and the analysis will really bebased on the ANOVA tables. Interaction between factors was determinedfrom the ANOVA as well as the interaction graphs provided by thesoftware. Finally conclusions must be made based on the analysis andresults.

The R₁ ratio developed strong effects due to each individual factor andthe interaction between Temperature and % Volume. All other interactionswere insignificant when compared to these four factors/interaction. Thiscan be seen in the ANOVA table in Table 4. The normal % probability plotand interaction plot (between Temp and % Vol) can be found in FIGS. 11,13 a and 13 b. Based on the analysis, the highest level for the R₁ ratiowould be with bacteria grown under the following conditions: lowtemperature, low light intensity, and high % volume.

TABLE 4 ANOVA Table for experiment. Note DF represents degrees offreedom and CE is coefficient estimate. An appropriate prob>|t| waschosen to be 0.01 for this output variable therefore A, B, C, and AChave an effect on this output. Factor CE DF Error Prob>|t| Intercept1.23 1 9.913 × 10⁻³ A-Temperature −.032 1 9.913 × 10⁻³ .0041 B-LightIntensity −.037 1 9.913 × 10⁻³ .0013 C-% Volume −.044 1 9.913 × 10⁻³.0003 AB .027 1 9.913 × 10⁻³ .0118 AC −.056 1 9.913 × 10⁻³ <.0001 BC.015 1 9.913 × 10⁻³ .1372 ABC −.021 1 9.913 × 10⁻³ .0502 Centerpoint .411 .024 <.0001

The R₂ ratio developed strong effects due to only temperature and nointeractions. All other factors and interactions were insignificant whencompared to temperature (see Table 5). The normal % probability plot andinteraction plot (between Temp and % Vol) can be found in FIGS. 13 a and13 b. As shown in FIG. 14 a, the results are so close to the linear linethat they are deemed insignificant except for temperature. Even theinteraction plots (FIG. 14 b) showed slight interactions. Note how thelines cross but the error bars overlap so that these lines could in factbe parallel and therefore non-interacting. The highest level possiblefor the R₂ ratio would be with bacteria grown under low temperature.

TABLE 5 ANOVA Table for experiment of R₂ ratio. Note DF representsdegrees of freedom. An appropriate prob>|t| was chosen to be 0.1 forthis output variable therefore A, B, C, and AC have an effect on thisoutput. Coefficient Factor Estimate DF Error Prob>|t| Intercept 1.23 1.047 A-Temperature −.11 1 .047 .0321 B-Light Intensity .032 1 .047 .5080C-% Volume .006 1 .047 .8990 AB .049 1 .047 .3050 AC −.035 1 .047 .4651BC −.036 1 .047 .4516 ABC −.077 1 .047 .1181 Centerpoint .51 1 .11 .0002

It is interesting to note from the results that the response variables(namely R₁ and R₂) are not dependent upon the same factors. R₁ issensitive to temperature, light intensity, and % volume and theinteraction of temperature and % volume. However, the R₂ ratio isdependent upon only the temperature during growth. This ratio was longbelieved to be only dependent upon light intensity but temperature wasmore significant. This may be due to the fact that the real dependentoutput is the R₁ ratio. If the bacteria are grown under those conditionsand R₁ changes, R₂ must change as well but not vice-versa.

It is also possible that the temperature affects only the 866 nmmolecules and light never changes growth (within limits selected in thisstudy). Another, stronger argument is that since the natural funnel-likeenergy transfer in the chlorosome (from 740 to 795 to 808 to 866 nmmolecules) protects the molecules further down the chain (like the 866Bchl a) from being sensitive to factors such as light. At the same time,these molecules are still protein based and very dependent upontemperature effects.

TABLE 6 DOE experiment calculated data for pigment-proteingrowth/development ratios over a period of 6 transfers (3 weeksapproximately). condition ratio Nov. 18, 1997 Nov. 21, 1997 Nov. 25,1997 Nov. 28, 1997 Dec. 2, 1997 Dec. 9, 1997 −−− 740/808 1.3182 1.21.1111 1.2174 1.25 1.0526 740/866 1.45 1.3333 1.1111 1.4 2 1.3333 −−+740/808 1.2381 1.1071 1.16 1.28 1.2308 1.1667 740/866 1.3929 1.12731.2889 1.4545 1.4545 1.25 −+− 740/808 1.1579 1.0345 .9231 1.1842 1.05261.017 740/866 1.2571 1.0526 .8571 1.2857 1.0909 1.3 −++ 740/808 1.23531.375 1.2027 1.1667 1.2 1.4 740/866 1.377 1.5068 1.3692 1.3462 1.35481.4848 +−− 740/808 1.3333 1.2222 2.0732 2.1458 1.88 1.125 740/866 1.45451.375 2.2667 2.4235 2.0435 1.1538 +−+ 740/808 1.6 1 1 2.3368 1.74121.9759 740/866 2 1 1 2.6118 1.9221 2.2162 ++− 740/808 1.2857 1.09521.1579 1.2917 1.2687 1.25 740/866 1.4062 1.2778 1.2941 1.4531 1.41671.3514 +++ 740/808 1.1111 1 1 1.3049 1.2273 1.3929 740/866 1.3333 1 11.4079 1.35 1.56 000 740/808 1.7105 1.7901 1.7901 1.5854 1.686 1.5224740/866 1.8571 1.9079 1.9595 1.6667 1.7262 1.619

Changes could clearly be seen from one transfer to the next. Thissuggests a forced evolution situation. The bacteria are being forced tosurvive in a hostile environment.

Take the +−− bacteria. In the first two transfers, it looked like it wasdying and then by the third environment, some cells have adapted to thedifferent environment and grown. Remember that the +−− was hightemperature, low light intensity, and low amount of food source. Otherchanges can be seen in this sequence of pictures but clearly, this wasthe most significant.

The light intensity and the light-temperature interaction factors hadcoefficients of only one half the temperature factor in the 740 nmvariable. This contrast was particularly apparent in those responsevariables that do not have photosynthetic activity. There is clearly acorrelation between the light factor, the light and temperatureinteraction, and the absorbance of Bchl c (740 nm). Since the otherresponse variables are mostly dependent on temperature, their changescan be primarily attributed to the change in absorbance which resultsfrom increased and/or decreased concentration of cells. Because cellularmembrane components have an absorbance of 650-700 nm, the concentrationof cells in each sample can be determined from the absorbance data inthis region. By normalizing the data, it is possible to extrapolate theBchl c absorbance for individual cells. This is the next logical step inanalyzing the data.

A method was developed to establish a faster process to count wholecells. A modified hemocytometry counting technique was used to countwhole cell C. aurantiacus concentrations (per unit length of 10 μm), andabsorbance data was gathered as three replicates of: 1:1, 1:1.1, 1:1.5,1:2, 1:3, 1:4, 1:5, 1:0, and 1:50 dilutions were made. Full spectra(absorbance) data was gathered for each dilution, as in FIG. 15 a. Eachreplicate was run to minimize instrument and operator error, FIG. 15 band peak data was gathered and averaged at 650, 740, 808, and 866 nm.The samples were then counted on an optical microscope using a standardred blood cell counting technique and a hemocytometer. In this fashion,curves were developed for absorbance at 650 and 740 nm and cellularcounts with error bars as in FIGS. 16 a and 16 b.

Counting Chlorosomes

For the purposes of characterization and conformity in preparing thehybrid devices contemplated, determining the quantity of chlorosomescoating the cover glass hydrophobic surface was important. Absorbance oflight was correlated to the density of chlorosomes as illustrated inFIG. 17. The calibration plot of FIG. 17 plots chlorosome count againstchlorosome absorbance at the 650 nm wavelength. The 650 nm wavelength ischosen rather than a wavelength where absorbance of the chlorosomeexhibits a peak because the absorbance at those wavelengths exhibiting apeak in the absorbance spectrum vary from one chlorosome to anotherdepending, inter alia, on environmental factors effecting the growth ofthe bacterium from which the chlorosome was taken. The 650 nm wavelengthabsorbance, then, is linearly related to chlorosome count and notanother variable.

In the exemplary preferred embodiment employing the chlorosomes of C.aurantiacus to enhance SiPV performance, chlorosome percent coverage ofthe SiPV's light receiving surface (or the overlying borosilicate glass)is important as demonstrated by the FIG. 19 plot of percent enhancementagainst percent coverage. Ideally, in this particular embodiment atleast, coverage should be in the 4 to 7% range and preferably about 4%.

To arrive at percent coverage, accurate counting of the chlorosomesbecomes important.

FIG. 1 is a conceptual block diagram that indicates the design anddevelopment of a hybrid device of the nature of the enhancedphotovoltaic cell described above. At each stage of development multiplevariables entered the design process. This is tabulated, as well, inTable 2. From this it will be seen that a robust program such as thedesign of experiments program that permits the assessment of multiplevariables and their interaction is an enabling design tool in arrivingat a final product that meets the objectives of high performance,robustness, scalability, energy interactivity and adaptability.

In the case of the enhanced hybrid photovoltaic device many pertinentissues arise at each stage of design. At the product stage, the deviceneeds to be tested using an appropriate light source and wavelength,such as a 470 nm LED or an incandescent light bulb with a correctinterference filter yielding 470 nm wavelength. Intensity is a variable.The use of suitable light waveguides or fiber optics may be a variableto consider. Stimulation time must be taken into account since it andintensity will correlate to a certain photostress that the device willbe able to handle or not handle if irreversible damage is to be avoided.Controlled environments and appropriate measurement devices are to bechosen.

Before the device can be tested, however, materials must be acquired,and/or produced as by systhesization. Here the stages involve growth ofthe bacteria and alteration if that is needed to alter the chlorosomesthat are to be employed. As has been seen, factors involved in thegrowth period can affect the chlorosomes, either beneficially or not.Some of these factors include light intensity, light type (i.e.incandescent, LED or fluorescent) and wavelength. Media (its PH,temperature, components, and strength) can affect chlorosome yieldingbacteria development. The number of days allowed for bacterial growth(either before isolation of the bacteria or before an exchange of media)is another factor. Bottle-filled volume or, as has been shown, percentmedia to air and temperature are factors, as well. Some of these factorsdirectly influence important design characteristics such as “Figure ofMerit,” discussed below, chlorosome size, chlorosome photostability,indirect quenching, etc.

Processing of the chlorosome requires isolation of the chlorosomes fromthe whole cells. As indicated above, this is done using procedures welldocumented. Nevertheless certain factors need to be taken into accountduring this process. These are the different procedures used to isolatechlorosomes without the reaction centers (i.e. the RC⁻ chlorosomes vs.the RC⁺ chlorosomes). Solvents, agents and buffer types used in theprocedure are also important, and factors such as the type, molarity,ionic strength, pH and strength of these all come into play. Thesefactors will affect the state of aggregation impurity of the isolatedchlorosomes, and consequently the ultimate success of the design.

Manufacture of the chlorosomes layer is the step whereby means ofimmobilization (which is to say, physical absorption) of a monolayer (ora percent of a monolayer) is deposited onto the surface of the substratesuch as the borosilicate glass. Here, important factors for successfuldevices include the fabrication conditions of temperature, incubationtime, lighting (on or off) and operation of a laminar flow hood. Sealingmethod, concentration volume and percentage of coverage enhanceinterparticle distances, dropment placement on the cover slip or in thewell, and cover slip hydrophobicity all bear on chlorosome placement andorientation (i.e. either facing the SiPV or the LED in the precedingexemplary arrangements).

Final product assembly involves many of these same factors just raised,others described above and other factors commonly encountered in productproduction. Further concerns relate to device lifetime, postfabricationstorage including temperature light intensity, type and wavelength areadditional concerns.

From the above, then, it should be evident that best guess or one factorat a time approaches to design and development pale in comparison to theDOE approach.

Figure of Merit

“Figure of Merit” (FoM) is a concept employed widely and in manydisciplines, although ordinarily not where biological matters arise. Inthe present invention a biophotonic Figure of Merit was devised toquantify chlorosome performance.

Bearing in mind the chlorosome functioning as conceptually diagrammed inthe block diagram of FIG. 21 a, the following Figure of Merit wasdevised.

${FoM} = {\frac{\%\mspace{14mu} T_{440{({{Bchl}\mspace{14mu} c\mspace{14mu}{Soret}})}}}{{\%\mspace{14mu} T_{440{({{Bchl}\mspace{14mu} c\mspace{14mu}{Soret}})}}} + {\%\mspace{14mu} T_{460{({Carotenoid})}}}}*{\frac{\%\mspace{14mu} T_{795{({{Bchl}\mspace{14mu} a\mspace{14mu}{Baseplate}})}}}{\%\mspace{14mu} T_{740{({{Bchl}\mspace{14mu} c\mspace{14mu}{Oligomeric}\mspace{14mu}{Qy}})}}}.}}$

This FoM takes into account the total transmittance of the Bchl c Soretat 440 nm as compared to the total Soret and corrotenoid 460 nmtransmittance and the baseplate Bchl a transmittance at 795 nm ascompared to the Bchl c oligomeric transmission at 740 nm.

Engineering to a Figure of Merit in the exemplary embodiment of thisinvention was calculated to yield 160% of the Vout response of theoriginal silicon photovoltaic cell at a Figure of Merit of 1.0. Theactual improved output was measured at 157%.

Although preferred embodiments of the invention have been described indetail, it will be readily appreciated by those skilled in the art thatfurther modifications, alterations and additions to the inventionembodiments disclosed may be made without departure from the spirit andscope of the invention as set forth in the appended claims.

Isolation, Separation and Harvesting Techniques for Light Antennas andSubunits

Books:

-   Chlorophylls, Hogo Scheer, CRC, 1991.-   Light-Harvesting Antennas in Photosynthesis, B R Green and W W    Parson, eds. Kluwer Academic Publisheing (Dordrecht: Kluwer), 1991.-   Photosynthesis: Photobiochemistry and Photobiophysics, Bacon Ke,    Springer, 2001-   Oxygenic Photosynthesis The Light Reactions, Donald R. Ort,    Charles F. Yocum, Iris F. Heichel, Springer, 1996.-   Chemicals from Microalgae, Zvi Cohen, CRC, 1999-   Physicochemical & Environmental Plant Physiology, Park S, Nobel,    Academic Press, 2005-   Molecular Biology of Membranes: Structure and Function, Howard R.    Petty, 1993-   Structure of Phototrophic Prokaryotes, John F. Stolz, CRC 1990    Journals:-   Yamnaka, G., et al., Molecular Architecture of a Light-harvesting    Antenna Isolation and Characterization of Phycobilisome Subassembly    Particles, J Biol. Chem., 257(8): 4077-4086, 1982.-   Lundell, D and A N Glazer, Molecular Architecture of a    Light-harvesting Antenna Structure of the 18 s Core-rod Subassembly    of the Synechococcus 6301 Phycobilisome, J Biol Chem., 258: 994-901,    1983.-   Montaño GA, Wu H-M, Lin S, Brune D C and Blankenship R E (2003)    Isolation and characterization of the B798 baseplate    light-harvesting complex from the chlorosomes of Chloroflexus    aurantiacus. Biochemistry 42:10246-10251.-   Simidjiev, I., et al., Isolation of Lamellar Aggregates of the    Light-Harvesting Chlorophyll a/b Protein Complex of Photosystem II    with Long-Range Chiral Order and Structural Flexibility-   Montaño, G A, Bowen B P, LaBelle J T, Woodbury N R, Pizziconi V B    and Blankenship R E (2003) Characterization of Chlorobium tepidum    chlorosomes. A calculation of bacteriochlorophyll c per chlorosome    and oligomer modeling. Biophys. J. 85: 2560-2565.-   Blankenship R E and Matsuura K (2003). Antenna complexes from green    photosynthetic bacteria. In: Light-Harvesting Antennas, B R Green    and W W Parson, eds. Kluwer Academic Publishing (Dordrecht: Kluwer),    195-217. 1991.-   Hu, D. and Blankenship, R. E. (2002) Rapid one step purification of    the BChl-a containing FMO-protein from the green sulfur bacterium    Chlorobium tepidum using a high efficiency immunomatrix, Photosynth.    Res., 71, 149-154-   Frigaard, N-U, et al., Isolation and characterization of    carotenosomes from a bacteriochlorophyll c-less mutant of Chlorobium    tepidum, Photosynthesis Research, 86:101-111, 2005.-   Qian, P., et al., Isolation and Purification of the Reaction Center    (RC) and the Core (RC-LH1) Complex from Rhodobium marinum: the LH1    Ring of the Detergent-Solubilized Core Complex Contains 32    Bacteriochlorophylls, Plant Cell Physiology, 41(12): 1347-1353,    2000.-   Cogdell, R. G., 1. Durant, J. Valentine, J. G. Lindsay, and K.    Schmidt. 1983. The isolation and partial characterisation of the    light-harvesting pigment-protein complement of Rps. acidophila.    Biochim. Biophys. Acta. 722:427-455.-   Cogdell, R. J., and A. M. Hawthornthwaite. 1993. Preparation,    purification and crystallization of purple bacterial antenna    complexes. In The Photosynthetic Reaction Center, Vol. 1. J. R.    Norris and J. Deisenhofer, editors. Academic Press, New York. 23-42.-   Clayton, R. K., and B. J. Clayton. 1981. B850 pigment-protein    complex of Rhodopseudomonas sphaeroides: extinction coefficients,    circular dichroism, and the reversible binding of    bacteriochlorophyll. Proc. Natl. Acad. Sci. U.S.A. 78:5583-5587.-   Cogdell, R. J., and A. R. Crofts. 1990b. Analysis of the pigment    content of an antenna pigment/protein complex from three strains of    Rhodopseudomonas sphaeroides. Biochim. Biophys. Acta. 502:409-416.-   Cogdell, R. J., A. M. Hawthomthwaite, M. B. Evans, L. A.    Ferguson, C. Kerfeld, J. P. Thornber, F. van Mourik, and R. van    Grondelle. 1990a. Isolation and characterisation of an unusual    antenna complex from the marine purple sulphur photosynthetic    bacterium Chromatium purpuraturn BW5500. Biochim. Biophys. Acta.    1019:239-244.-   Cogdell, R. J., and J. P. Thurber. 1979. The preparation and    characterization of different types of light-harvesting    pigment-protein complexes from some purple bacteria. In The CIBA    Foundation Symposium 61 (new series) on Chlorophyll Organisation and    Energy Transfer in Photosynthesis. G. Wolstenholme and D.    Fitzsimons, editors. Elsevier, Amsterdam. 61-79.-   Evans, M. B., A. M. Hawthomthwaite, and R. J. Cogdell. 1990.    Isolation and characterization of the different B800-850 light    harvesting complexes from low- and high-light grown cells of    Rhodopseudomonas cryptolactis. Biochim. Biophys. Acta. 1016:71-76.-   Yokthongwattana, K., et al. Isolation and characterization of a    xanthophyll-rich fraction from the thylakoid membrane of Dunaliella    salina (green algae), Photochem. Photobiol. Sci., 4:10288-1034,    2005.-   Mrquardt, J., et. al., Isolation and Characterization of Biliprotein    Aggregates of Acaryochlris marina, a Prochloron-like prokaryote    containing mainly chlorophyll d, FEBS Letters, 410:428-432, 1997.-   Adam G. Koziol, Tudor Borza, Ken-Ichiro Ishida, Patrick Keeling,    Robert W. Lee, and Dion G. Durnford, Tracing the Evolution of the    Light-Harvesting Antennae in Chlorophyll a/b-Containing Organisms,    Plant Physiology, April 2007, Vol. 143, pp. 1802-1816,    www.plantphysiol.org, 2007 American Society of Plant Biologists-   X. Hu, et al., Predicting the structure of the light-harvesting    complex II of Rhodospirillum molischianum, Protein Sci, 1995 4:    1670-1682.-   N Nagata, R Tanaka, S Satoh, J Minagawa, A Tanaka, Isolation and    characterization of a gene for chlorophyllide a oxygenase from    Prochlorothrix hollandica, Endocytobiosis Cell Res., 15: 321-327,    2004.-   Andreucii, F., et al., Isolation of phosphorylated and    dephosphorylated forms of the CP43 internal antenna of photosystem    II in Hordeum vulgare L. Journal of Experimental Botany 2005    56(414): 1239-1244.-   Andrew N. Webber, Rapid Isolation and Purification of Photosystem I    Chlorophyll-Binding Protein From Chlamydomonas reinhardtii,    Photosynthesis Research Protocols, Methods in Molecular Biology,    Volume: 274: 19-28, 2004.-   B R Green and D G Durnford, The Chlorophyll-Carotenoid Proteins of    Oxygenic Photosynthesis, Annual Review of Plant Physiology and Plant    Molecular Biology, Vol. 47: 685-714, 1996.-   Observation of the Energy-Level Structure of the Low-Light Adapted    B800 LH4 Complex by Single-Molecule Spectroscopy, Biophysical    Journal, 87: 3413-3420, 2004-   Zhang, S-J, et al., Energy Transfer among Chlorophylls in Trimeric    Light-harvesting Complex II of Bryopsis corticulans, Acta Biochimica    et Biophysica Sinica 38(5): 310-317, 2006.-   Planck, Tracy, et al., Subunit Interactions and Protein Stability in    the Cyanobacterial Light-Harvesting Proteins, Journal of    Bacteriology, 177(12): 6798-6803, 1995.-   Bibby, T. S., et al., Low-light adapted Prochlorococcus species    possess specific antennae for each photosystem, Nature,    424:1051-1054, 2003    Reports:-   Structure, Function and Reconstitution of Chlorosome Antennas from    Green Photosynthetic Bacteria, Robert E. Blankenship, Final Report    DE-FG03-01ER15214, DOE, September 2001-August 2004    Theses:-   Hu, D. (2001) Investigation of the Fenna-Matthews-Olson protein from    photosynthetic green sulfur bacteria. Ph.D. Dissertation, Arizona    State University, Tempe, Ariz.-   LaBelle, J T, Design Feasibility of a Nanoscale Biophotonic Hybrid    Device, PhD Dissertation, Arizona State University, 2001.

1. A hybrid photoactive device comprising: (a) a photoactivenon-biological component; and (b) a plurality of Reaction Center Minus(RC⁻) chlorosomes; wherein the photoactive non-biological component isdisposed in the path of light emitted by the RC⁻ chlorosomes.
 2. Thehybrid photoactive device according to claim 1 wherein the photoactivenonbiological component is a photovoltaic cell.
 3. The apparatus ofclaim 1, wherein the RC− chlorosomes are directionally oriented.
 4. Theapparatus of claim 1, wherein the RC− chlorosomes respond to incidentlight by emitting emitted light that differs in wavelength from theincident light.
 5. The apparatus of claim 4, wherein the incident lightis in the visible range and the emitted light is Stokes-shifted withrespect to the incident light.
 6. The apparatus of claim 1, wherein theRC− chlorosomes are adsorbed on a substrate.
 7. The apparatus of claim 1wherein said photoactive nonbiological component comprises aphotoconductive component.
 8. The apparatus of claim 1 wherein saidphotoactive nonbiological component comprises a photoemissive component.